I have an idea for it. I know it'll be complicated, but what if it gained only +1|+1 when you used develop, but created a "Technology" card of some kind.
Edit: Have the technology cards be some kind of amplifier. This caveman can create any sort of random technology cards, that have the power Equip: Sacrifice <Insert Name> Technology to <Insert Effect> target creature...
For example: Efficient Technology: Sacrifice Efficient Technology to reduce cost of target creature's active ability by 1