Greetings!
I've only recently been invited into the beta, and while I installed the game about a week ago, I haven't had the time until now to actually get into the game. My initial experience is: You folks have done an Incredible job so far!
When I first bought WoM back in 2010 I really tried to get into the game, but it never had that 'hook' factor. Patches since have helped but none of them left me with the feeling that I felt almost immediately upon loading FE for the first time. 
That being said, there are a few things that feel a little out of place and while I realize this game is still in beta, perhaps for that very reason it seems appropriate to state them here. Apologies in advance because I'm sure at least Some of these have already been expressed by others..
1) (Game Feature) The dynasty system was one of the things I really enjoyed most about WoM. It added a fun RPG element that many other strategy games lack and I really Really hope it will return before the game goes live.
2) (UI) As others have said on this forum, the movement controls are sort of wonky. There is no fluidity when one scrolls the map, sometimes it hitches other times it lurches (when the cursor is moved to the borders). The click-drag system works, but it would be really nice if scrolling could be improved. I'd really like a variable scroll feature ~ one that starts to slowly move as you approach a screen edge, and moves faster the closer you get to the edge. This sort of 'control' over the world really improves the experience imo. If possible, please make the mouse scroll directions reversible in the options, rotation as well.
3) (Game Setup) I love being able to create factions and customize leaders! This is something that I've always enjoyed in games like SMAC and MOO2. Now it's a minor issue, but it would be fun to also be able to 'edit' my creations after the fact, so that if I just want to tweak something, I don't have to start all over from scratch. Maybe I just want to use that same character model that I've created but give my ruler different perks?
4) (Combat) During the tactical combat, I've noticed some peculiarities with the cursor. When I go to make a melee attack against an adjacent foe, the tooltip popup sometimes obscures the cursor and makes it difficult to make the attack. The attack cursor itself also tends to blink while it's doing this, which is sort of frustrating. Perhaps the popup could be moved to the top of the screen or off to the side so that it isn't directly interfering with the units being examined and selected?
5) (Combat) Speaking of the info popup over units, if I want to examine a unit on the tactical screen by hovering the cursor over the unit, it only shows the basic attack/defense/movement info and sometimes it doesn't even pop up at all. I can get more detailed info by clicking on the unit's image on the initiative queue, but it'd be nice to be able to just left click on the unit itself to see that info.
6) (Combat) It would also be great to have more of an idea of where my character will move to before they make their melee attack. The way it works now, if you hover the cursor over a target, you only see the cursor change to attack (crossed swords) but you really can't tell what square the game will move you to before you make that attack. You can move first and Then attack of course, but it'd be even better to have the squares themselves highlight while the attack cursor is hovering over them so that you can easily see which spot you'll move to first. The more recent HoMM games use this feature to good effect. Position is very important in the battle already, but it could be made even more so if tactics like flanking and backstabbing/blindside attacking are ever incorporated.
I hope these ideas help, and thanks again for continuing to improve this game!