What's the MLB Rule? Do they require 25 active players on an ML roster at all times? I'm not sure, but I think they set a maximum, not a minimum. If there is a minimum, HBD should match that. If MLB does not have a minimum, then HBD shouldn't either. If I have iron horses, what's wrong with me going as far into the season as possible with 24 (or fewer) players. Maybe all season.
The demotion penalty, as it works now, is just silly. I listed a few alternative that would make more sense in that thread. Minimum number of days before a player can be promoted or demoted again. Impacts that player resigning, including MinL contracts. Impacts other players resigning with that team and/or GM (if the GM changes, the I Won't Resign logic could be removed).
Keep the silly loss of skills, but tie it to length of time at a higher level & quality of play. Players who are promoted at the end of one season should not get a penalty if they are demoted at the start of the next season (even if it's after spring training). Players who performed below average should not get a penalty if they are demoted.