Unfortunately, the clan competitive circuit, is really the main determining factor for what settings are played in the MP lobby. The majority of games are practicing for competitions, which have a standard set of rules, use mostly the flat grassy plains map, and have limits on how many of each type of units you can have and limits on what units are allowed. This leads to new players being forced to play at certain settings, unless they host their own games. Even then it takes awhile before people will join those games.
Myself, I like playing with all the different florin levels, 5k through 20k, all the maps (except those with buggy deployment zones). I would experiment with different unit sizes, but unfortunately, for bigger games the host must place the units on small unit size to accomodate those who have less than new PCs. I cannot play a 3v3 or 4v4 game on normal setting without a lot of lag, since my PCs are the same ones I use for MTW1. hehe :)
Bookmarks