Whats the point? Could you not just change the Genesis Block, hardcode it into your bitcoin core and basically create your own blockchain?
Then mine for few hours... you will have your own block chain with hundreds of your own tBTC. For free.
Yeah, definitely be better off using RegTest... you don't need to change/recompile anything... it's basically an "instamine" and you can freely test whatever you want. Refer:
https://developer.bitcoin.org/examples/testing.html#regtest-mode