On Warhorses vs Horses:
They have a minor advantage over regular horses in that the first turn bonuses are 50% higher (meaning +3 attack and initiative on the first turn rather than +2 attack and initiative). But they are also nearly twice as expensive to purchase for champions, aren't any faster, and, unlike wargs, don't provide an ongoing bonus for the duration of the battle. Since by the time I'm likely to be fielding significant mounted forces I'm also unlikely to care too much about a difference of one or two attack points per figure on any given unit (especially champions), I don't find it that valuable.
Of the two bonuses granted by Legacy of Serrane, I'd say that the Bazaar is better. Even if you don't make use of the Produce Wealth option that much, the 25% rush discount is handy when you want to finish something quickly or rapidly acquire a new unit. Indestructible caravans were nice back in War of Magic when completed caravan trips improved the quality of the road and the bonus granted for the trade route; however, I don't think that that aspect of the game survived even into Fallen Enchantress, so it's kind of pointless now aside from the nuisance value of being blocked by a 0-attack 0-defense unit which cannot be attacked by your big army of knights or whatever you use.
On the Lucky Trait:
I'd say that Lucky isn't really the best fit for Capitar, as they don't really need the accuracy bonus, and the dodge bonus is somewhat wasted on them. Dodge-based units are very heavily dependent on starting off with lots of dodge, because the difference between accuracy and dodge is, in the best case scenario, only going to remain constant as the unit levels increase (this, of course, is assuming that the AI actually manages to preserve some of its troops to get them to a decently high level, similar to that of dodge troops). Plus, if someone starts stacking the Accuracy bonus repeatable tech you'll rapidly see your chosen defense become meaningless as, unlike attack vs defense, there is no repeatable dodge bonus tech, and moreover since the bonuses are percentage based you'd be outscaled anyways since basic units start with about twice the accuracy that the best dodge-centric units start with (which requires Wraith Blood, and since Capitar is not a Wraith faction, you're looking at something closer to accuracy numbers roughly three times better than your starting dodge). As a result, dodge is exceptionally unreliable at higher difficulties, and tends to be more of an early to mid game toy even at lower difficulties.
Civics is also a bit of an odd one, as it's just a slight head start in research and doesn't provide any ongoing bonus (unlike Scholars, which gives Knowledge and a 10% research bonus).
Escape ability is my least favorite one, because it almost does not 'escape'. The only thing it does is to return you to square one of the problem.
Escape isn't a bad ability as long as no members of the army were immobilized during the engagement and as long as you had sufficient movement points to attack the monster and move afterwards. It's more of a hit-and-run type ability than an escape ability, though.
also: I believe I made a big noob mistake: I made general Carrodus a commander instead of a warrior, defender assassin or mage. This seems really bad because I want him with my main army because of his +25% experience and +1 initiative for the whole army -and for his cautious escape ability. I keep him in an army with Bacco the Beggar because Bacco is a Capitar (moves 3) and doesn't slow down the army.
Honestly, I'd sooner have a Commander sovereign than a Warrior, Defender, or Assassin sovereign, because when specialized for field command, the bonuses are quite useful. Carrodus even has a head-start here - he doesn't need to wade through the Leadership traits to get to the Tactician traits, which means that he can get to Battle Cry relatively easily (although I think that one is level-restricted, so it isn't exactly coming early); moreover, the Tactician traits provide a bonus to the initiative of your whole army. You thought Fast was good for your units? How about Fast on all of your units free of charge? Because that's essentially what Tactician I + II gets you, and you can have that by your third level. Beyond that, Command and Battle Cry are amazingly useful abilities, particularly for a high-initiative sovereign.
Carrodus himself also isn't that much of a Mage, since his starting magics are Air I and Life I, neither of which gains that much from the bonuses present in the Mage tree since Life and Air are more defensive support schools than offensive support or offensive damage schools. Two curses, two damage spells, and two healing spells - that's all that Carrodus can get that has a direct benefit from Path of the Mage; everything else is blessings and strategic spells, and while tactical blessings benefit from the mana discount, strategic spells do not. Plus, Air Magic tactical spells tend to be relatively cheap to cast (especially Haste, which is nearly free and is in my opinion the best tactical spell available at the first level of any magic, and one of the best tactical blessings in the game).
Is there anytime that making your sovereign a commander is not a bad choice? Can you offer any advice on playing as The Capitar? Thanks in advance
My opinion on champion classes is "if it doesn't make a good mage, make it a commander, because I can fill all the Warrior/Assassin/Defender type roles I need in most situations with trained troops, and commanders additionally have better noncombat bonuses even if you don't work up the Governor side of the tree". Warriors/Assassins/Defenders tend to be outclassed fairly heavily by mid-to-late game trained units unless you found enough good equipment to share around (or unless you're only using one or maybe two such champions); however, since I tend to play slower, longer games with big empires, it's the mid-to-late game troops that I'm concerned about my champions facing, not monsters and early-game garbage units. If you like faster games, or get into wars earlier, then it's possible that Warriors/Assassins/Defenders will serve you better than a Commander, or even perhaps a Mage, would.
Advice for playing Capitar: use your Pioneers to build roads to the city you're using them to found as they wander towards the city - it doesn't cost you much time, and it gets a road there quickly and along a good route (assuming you plan ahead). If you want, edit the Scout design (or a different basic unit, or create a custom design) so that it has the Road Building trait, and use those to rapidly survey the map and pave the way for your armies of conquest and hordes of pioneers to come out to take over the map - but remember that roads in neutral territory provide the benefit to anyone who comes by, and roads that you build in hostile territory don't give you any bonus until it becomes friendly territory.
Get non-Mancer champions that you're using as army commanders mounted as quickly as possible, or they'll really slow your army movement (alternatively, focus on getting Mancer champions for army leadership). Warhorse-mounted Mancer units lead by a (War)Horse-mounted Mancer champion constitute the fastest army in the game, particularly if you put Tireless March on that champion, while Warg-mounted Mancer units can keep pace with (War)Horse-mounted non-Mancer champions, and Mancer infantry can keep pace with Warg-mounted non-Mancer champions. You're highly mobile, put that to use running down enemies or avoiding big armies, raiding, and striking deep into the heart of enemy territory.
Legacy of Serrane + a sovereign with Air I practically begs for at least one high-essence Town that built only the gold-production improvements and spends most of its time producing wealth. Doing this will allow you to support much larger armies early on if your capitol or some of your early cities happen to be Towns of that type, and once you have one or two of those you're probably all set for gold production until much later in the game (meaning you can skip the Merchants in other cities, and skip out on making more Towns aside from Wonderville and New Wonderville for the rest of the early and part of the mid game). Merchants and Markets are all you really need for gold production, and getting a Grocer and a Well or Inn if you want them won't take that long; besides which, gold income is unaffected by unrest and production, so you need not build workshop/lumber camp and cleric/bell tower line buildings in Towns until you want to start getting high level improvements or unless you've built a large enough empire to have very poor construction rates without such buildings.
Mancers have an enormous advantage in the early game with their extra movement and road building, as they can explore and expand more rapidly than any other faction save perhaps Tarth, which lets them find other factions while they are relatively weak, and also permits a hit-and-run raiding style to kill off weak armies or force an enemy to spend lots of time rebuilding world resources (or cities, if you want to take a city but don't really feel like holding it - you can raze improvements to cripple the city even if you can't raze the city or don't want to, and the 'recently conquered' unrest penalty will hit the faction that takes the city back the same way it hits you). Later in the game as mounted units (and start-of-battle movement traits) start coming into play, the movement bonus begins to degrade from a relative utility perspective, but it still keeps your infantry relatively more useful than the infantry of other races simply due to the mobility, and it can allow you to delay Mounted Warfare/Warg Riding research and Stable/Kennel construction longer because you simply don't get as much out of it.