Stical- parts I would recommend getting would be- A spare rear axle hub, the left side or non diff side, they do crack or strip, Also get some spare 4-40 wheel bolts for the rear, and the 2-56 bolt for the hub, all other screws are metric in the car, all wrenches are metric, except rear wheels are 3/32, a .o50 size wrench is good to have, and the diff wrench,(11/32 I think).
Spare shock rebuild kit or 2 is good, spare side springs, both different ones and the same as kit, it is very possible for a side spring to fall out.
Spare set of front end blue spacer washers is good, and a spare shock shaft, they do bend from batteries hitting them, or piston coming loose from the shaft, spare blue shock end would be good for the same reason. Front end springs would also be good to have...
Other than some shock and hub issues, I have YET to see a broken part on a 12R5 since they have come out, that is at 3 different tracks in the area with ALL different skill level drivers, very durable car, I myself would NOT recommend the aluminum screw kit, there is not many screws in the kit, and most thread into metal, it sucks to strip a screw head and try to get it out, steel is much more reliable, won't save much weight anyways...