I've just played through my, what, fourth full game? Not to say I haven't started more than four, I just never finished more than four.

Anyways, do you guys tend to use frigates and cruisers (if cruisers at all), pure capital ships, or a mix? I usually don't bother with capital ships and go straight for the frigates. The only cruisers I ever built were the light carriers, mainly for their bomber support (still so overpowered~!). I mass them, but just enough to plow through the computers' defenses (I doubt they'll be any good against a human), something in the thirties for Light Frigates and Missile Frigates, and tens for Anti-Fighters and Sieges. I build the Heavy Frigates when I can. I tried the Command Cruisers too, something like twenty.
Which is my next question, do you guys think Command Cruisers have any effect? I don't really notice a substantial difference, but maybe I don't have enough? Twenty Command Cruisers for a group of 100+ frigates?
And do you guys research upgrades early on or sit on them until you have a fleet already and then start thinking? I stopped researching them because I think that 1 or 2 points extra damage doesn't change much when I could build some 5 frigates for the price of research.
Thoughts?