Well the Arverni are quite easy to play, if you don't care about leaving the Aedui to survive.
If you want, you can easily destroy the Aedui in Transalpine Gaul. Just attack them the first turn, take Bibracte, and after that Cenabum. Then you can disband most of your army and eventually (very soon) you will be able to have a lot of money.

Also, the cavalry is very expansive, so try to disband them the moment you don't need them