-snip-
you'll likely wont be able to mine any more blocks using the same hardware after the next difficulty retarget if you generate blocks too fast.
You won't be needing too much coins in Regtest anyway since you can send satoshis instead of whole coins for tests.
From the above, you can skip editing consensus.fPowAllowMinDifficultyBlocks and consensus.fPowNoRetargeting to keep retarget disabled.
Just the consensus.nSubsidyHalvingInterval to copy mainnet's halving.