1v1 - It has to be strategic, however much stick it gets for being repetitive, it still have over 100 players on ladders, the 1v1 RT game fills up every minute or so and it is the most played template on warlight without a doubt.
However there are other good 1v1, such as strategic Turkey, East Asia & Oceania and even Eu is sometimes ok on 1v1.
2v2 - Strategic 2v2 is a very fun and interesting template as well, since there are only two picks you must choose correctly between quick combos or coverage of the map.
Also szewuropa is starting to grow on me, and one I did this morning was very close, and it relies on reading the opponent, as bonuses are much fairer, all 5 territories are worth 3 for example, taking some focus away from centre and islands and more towards Russia and Balkans, as the bonuses are larger.
http://warlight.net/MultiPlayer?GameID=4329016
3v3 - Europe 3v3 is one of the most played 3v3 templates, because the map was so well designed by Troll to make it have several different main fronts (centre/islands/Russia/Balkans etc) and even if one player is eliminated in the first couple of turns from a team it doesn't mean they will lose.
http://warlight.net/MultiPlayer?GameID=2746128
Eastern Asia is often played as a 3v3 map, but not nearly as much as Europe, which I think is bad, though the map is very large and not equal, there are so many different possible good bonuses that the games become pretty interesting, however mostly decided in the first couple of turns, as players often go for the same bonuses.