So, I haven't seen much on these forums about actual gameplay. What's good when, and against what? Where and how often should I click on my screen?!? What buttons should I press?!?

Lets fix that.

For early game, when/what do you focus on? Getting radioactives early to get cruisers out quickly, or focusing on metal to obtain area control at the expense of the concentrated firepower that cruisers can bring? 

I've found that frigates become increasingly inefficient cost wise as battles get larger and the frigate to cruiser ratio gets larger than 10:1. If the enemy army has a lower frigate/cruiser ratio, then size effects that ratio even more. Eventually, the melee range frigates become essentially useless because of all the long range AOE damage if the opposing army has any number of artillery cruisers. They simply don't live long enough to put out any damage, and their relatively high health per metal doesn't end up helping because its spread around 5 units. The artillery frigates remain useful for far longer because they can sit behind the cruisers and rain death from on high. 

As for late(er) game, when we start to see dreadnoughts, everything changes again. The artillery frigates become less effective because health is concentrated in fewer, larger units and at this point their DPS is just not enough for their population cost. Melee frigs, on the other hand, become very effective as an excess metal sink because they can tank the often overwhelming single target damage through overkill. 

If I am attacking a fixed position supported by an army, is it better to have an artillery dread with close range support units, or artillery units with a support/assault dread? Is the massive upfront damage of the assault dread actually better at breaking some types of defenses than the artillery dread, since it tends to evaporate structures? 

I've found that the assault dread, if supported well and managed properly, can very nicely fulfill the saying "the best defense is a good offence". Wreckage doesn't fire back. 

All joking aside, aots (that's almost pronounceable, so lets go with it) seems to do a pretty good job rewarding players for actually thinking ahead, and think sideways. In my opinion, the game has the same 'feel' as the board game go, which is about the highest praise I think a RTS can get. Starcraft, for example, plays like fast chess. That isn't necessarily bad, but it definitely focuses on builds and timing, giving a very different feel that I happen to enjoy less. If I want to memorize 'builds', plays, counterplays and see how well I can execute them under time pressure, well, I'll just go play fast chess:)