Sounds like you are a perfect owner for a
BX2200. You've probably done more maintenance than most tractors get in their lifetime. Be sure to keep it up at the factory recommended intervals.
If you search this forum for
BX2200 problems you'll come across some areas to keep an eye on. Your MMM will generally protect the transmission (HST) fan but a guard, either homemade or purchased, would be a good investment.
Hydraulic hoses are a problem after time so keep an eye out for leaks, especially under the center of the tractor. The lines from the pump to the power steering are a bit lightweight and prone to failure IMO.
Check to see if your air filter bracket is broken and the air filter flops around. If so, that will need attention. The engine shakes like a belly-dancer at low RPMs and when shutting down so a direct bracket replacement will be prone to failure also. Try to fab up something stronger.
One way to take the stress off the machine is to increase the idle until the engine smooths out. Warm-up goes quicker and the shaking is minimized.
The switches on the dash REALLY don't like to get wet and will short out causing lights to flash and a dead battery the next morning after parking it. The lights go on whenever they please as if haunted. You can pop out the switches and disconnect the pigtail. The lights are pretty useless anyway unless traveling down a road or working on the shoulder.
If you are doing something heavy duty and the HST seems to stall, switch to low range. It is much stronger.
Enjoy, and, if problems arise, check back here. Lots of members have used that model and have worked out fixes.