I made a rom hack all by myself and holy moly it took alot more time then I expected. If you want my help I can help you.
Not much is difficult just time consuming, experimenting and balancing. The testing part is really fun tho and it feels really good when something works :3.
I recommend using Advance trainer and Advance map to make a rom difficulty enhancement first (which I have done) still took me a load of time :/. Also if you need anything script-wise use XSE and Advance text you can find it on wahack (google it) If you want me to help you with your rom hack send me an e-mail:
[email protected]