Ruts: You will find that most 4AGE setups are east-west. There were very few RWD cars that came with the 4AGE (mostly AE86 etc), not counting the MR2 because the MR2 has basically got a FWD setup, but behind the driver instead. This is what a friend of mine is doing with his DIY sports car, with a silvertop 4AGE.
Contrary to popular belief, drum brakes aren't weaker than disc brakes. In fact, in some cases (and I stress the "some" because disc brake technology has come a LONG way) drum brakes offer greater stopping power than discs. The main problem with drum brakes is the heat and gas, as they cannot dissipate heat anywhere near as quickly as discs, and tend to develop envelopes of gas around the shoes, making braking rather ineffective.
At the end of the day, it is up to you what you would like to do, and what your engineer sees as appropriate. I have seen cars with ridiculously powerful engines and tiny stock brakes, in my eyes I see them as moving coffins. But that is just me, and obviously some other people see differently. At the end of the day, it is up to you.