Does it suddenly get more interesting? No. But I'd suggest that it's up to you to make it interesting. So you have two mages? They shouldn't be specced similarly at all (well, except for the fact that you'll want to pump their INT a fair bit). You know that fire on water makes steam, so make one wizard with a higher initiative and give him/her hydro, aero and geo; give the other one pyro, witch, and aero. Let the one who acts first lay down water (to control fiery areas) or ooze (for damage) and then blast it all with your pyro. If you've laid down water and then steam it, when the next turn starts you can shock it to make it a roiling bundle of stun and then start teleporting stray monsters into the middle of it - they'll take falling damage, damage one other enemy if you make them land very close, and then they'll get shocked and stunned by the storm cloud you've created. Anyone who gets away while teleport is on cooldown can be blinded or just blown apart.
By about level 10, though, both mages should have at least one point in each casting skill, just because it's great to have redundancy (blind is so sickeningly powerful that it essentially makes any fight you want into a purely, perfectly controlled massacre of the helpless - at least for the first twelve levels or so - I haven't finished the game yet). You won't find anything like the dizzying array of options in 3.5ed D&D, but as long as you plan your party as a whole, and not as four individuals who happen to be walking in mostly the same direction, you should have plenty of distinctiveness available to you.
Last edited by OneFiercePuppy; 05/07/14 03:07 AM.