Allies "dominate" in 2v2 more than anything. Well, "dominate" is saying too much, it is by no means a foregone conclusion, but win ratios at the higher levels of play are definetly in their favour. I concur with you though that Cons could need a little love, still, con builds can be played very successfully in 1v1.
According to Legends data, Axis are doing extremely well in 2v2.
his/her data from 9-15-14 to 9-25-14 show that
Win ratios:
USSR: .546
USA: .560
OKW: .781
OST: .689
Source: http://community.companyofheroes.com/forum/company-of-heroes-2/coh-2-balance-feedback/106966-win-lose-ratio-from-15-9-25-9-2014-much-more
Unfortunately, his latest set of data (https://docs.google.com/spreadsheets...it?usp=sharing) does not include 3v3 or 2v2 win ratios, but Legends says that the data hasn't changed much. We can assume that the numbers have stayed relatively consistent.