Promote every MinL you want around next season. You may or may not buy into it helping development, but I doubt it hurts. Exception to this is anyone ready for the ML if you want an extra arb year. Keep them in AAA and promote 24(?) games into next season.
Demote or release borderline players on your ML roster you don't want to pay $350K+ next season.
Look at your departing ML FAs. Sign anyone you want to keep if there is any chance they'll be Type A or B. Type A's will rarely sign with you next season unless you make a huge offer. Type B's more likely to sign next season, but why risk it? If a player is aging and you expect their ratings to drop, usually they'll ask for less next season. Easy call if they won't be Type A/B. Gamble if they might be Type B.
Look at your departing MinL FAs. If they are any kind of prospect, put them on your 40 Man. No harm releasing vet FAs you don't plan to resign who won't be Type A/B.
Check option and arbitration reports. Decide who's staying and who's not.
Spend all your $$ until you fill your MinL rosters. Sign draft picks, MinL FAs (this one you have to do the last week of regular season, they won't sign after that), & maybe even 1-2 Tryout Camp filler. Most of them won't retire. Less work to do at the start of next season. Worlds can run out of players if enough GMs don't sign their draft picks and keep 27-30 players at each MinL level. This one is as much of a community service as anything else.
I rarely release MinL filler. I will put them in LoA or Rookie and dare them to retire. I'll take any warm body at those levels next season. Every warm body I start with is one less I have sign next season.
Look at the FA report for next season. Anyone worth targeting? You can start thinking about budget for next season.
Look at your coaches. Compare to others at that level and look at the level(s) where you're best prospects will be. You can't control coaching staying or going, but you can start to think about maybe raising or lowering your coaching budget for next season. Coaching hiring SUCKS. Sucks a little less if you have a reasonable budget going in.
Study what works. Look at the roster of the playoff teams (you can do this in other worlds, too). What do you see there? What kind of role players do they have? How much to they pay them? Everyone knows a player with 80+ ratings across the board is a stud worth big money. Winning is identifying value everywhere else. Look at the 100 loss teams. What do you see there? Don't copy that.