Well since not much hacking is going on here is a xp exploit if you have time.
Get a couple people willing to play for a couple hours and do a One Man Army Match.
Set kills to watever. Try to have a full lobby.
Say you set kills to 45.
Do a deathmatch till someone hits 40, and let someone get 45.
Almost everyone will get xp.
Another is CTF
Me and my cousin would switch off wins and get lots of xp fast.
These may be kinda useless but help lvling if you have time.
Post more if you have any.