I've thought for a while, that a nice 1901 twist would be as follows (inspired my other progs). Start in 1901. Random snake style draft. 12 teams - 2 leagues. 40 win-minimum for the 1st. No rotation or position players below 80% fatigue. Players can play out of position, but only if it follows the CF-SS-2B-ect rule. Bones players for the first few years.
The Shaft twist = players who first appeared in an MLB year, but didn't meet the 50ab/25ip threshold, are eligible, in the 1st round only, to be drafted as "prospects". Teams can have 1 prospect at a time. Teams that select prospects would have to pick a supplemental pick at the end of the regular draft. 2 AA real-life prospects to help with trading and filling out rosters.