http://www.freewebs.com/dominions2/ has a lot of useful stuff. For example, it has a list of the hotkeys, and it has a list of all the tips you get between turns.
I do think you're perhaps slightly missing the point with Dominions 3. It's a long way from perfect, and it doesn't have the polish you'd expect from a game produced by one of the major software houses. "Quirky" would be one way of describing it. However it's clearly designed by someone who loves fantasy and loves strategy games, and who has gone to an enormous amount of effort to produce something which is fun to play. I've never seen anything quite like it in terms of the depth of the mechanics and the variety of options available. If you like that and are prepared to put up with the quirks, then I think you'll enjoy yourself. If it's not for you, well there are plenty of other games out there.
Regarding how responsive the developers are, although I'm not sure how regularly they read these forums, clearly the game has been developing steadily for several years now, so if you make sensible suggestions that don't go against their design decisions and can easily be introduced, I'd have thought you have a reasonable chance of seeing them being adopted at some point. Don't underestimate the complexity of some of the things you've asked for though. For example, although I think having squads stick together is a sensible suggestion, how would you code it exactly? What should happen if the squad gets split up in combat, for example?
If the game is to ever get a major commercial release, I think the battles would have to be rewritten from the ground up, but the approach of the developers seems to have been to stick with an engine which has major limits but works in its own way, and concentrate on making the multiplayer side as enjoyable as possible (lots of possible strategies, reasonably well balanced). With a game like this you kind of have to accept it as it is; the developers don't seem to be in it for the money, and they're going to concentrate on the bits which interest them and they have the resources to deal with, rather than making the whole thing amazingly polished. But if you compare it to, say, Heroes of Might and Magic V, that game had amazing graphics and lots of polish, but to be honest I found it quite dull. I may go back to it (I loved the previous versions), but you spent a lot of time doing exactly the same things as in HoMM III, only with better graphics, a worse story and not very exciting maps. There just wasn't enough there to interest me. Dominions, on the other hand, is idiosyncratic to say the least, but the ideas are extremely original, and the amount of options in terms of what to do is staggering. You could spend 100 hours playing it and not scratch the surface of the different strategies available.
I know which game I'd prefer to play.