I'm finding the lowest setting way too easy. So far I've played about 7 league games and won them all scoring 27 and conceding none. three of the games were 5-0 and the lowest has been 2-0. However I lost my league cup game to Luton 1-0 after resting loads of my players and conceding a goal from a corner. Made me laugh though that I found it much easier to play against Arsenal (one of the teams I beat 5-0 and should have had many more) but lost to Luton.
In reply to who people play as online. Arsenal, Chelsea, Real Madrid, and AC Milan are the favourites. I always select a team of a similar skill rating so that things are more even. I lost one game to some Austrian team 1-0 after the ball bounced of Neill and went in the net in the 90th minute.