quick search for "round bailer" and see a range between 40 to 100 HP at the PTO. the larger the HP at the PTO the larger the round bailer you could get for larger round bails.
Round Hay Baler | Case IH
John Deere Round Balers
15' bat wing rotatory cutter. (bush hog) quick search showed min 45 and high end of 200+ HP at the PTO.
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size of the machine, you might look into any sort of "monitoring equipment" for newer round bailers. or if you plan to use the tractor for GPS navigation for field work.
check on creeper gears. (lower gear ratios)
if field work besides bailing, perhaps rear dully option 4 tires on rear vs 2.
round bail spear for the FEL (front end loader) and making sure you have enough counter weight in the rear. to stack round bails 2 high. other words rear tire weights or filled rear tires, or 3pt hitch ballest box/weight box. or some other heavy weight 3pt hitch implement.
if you are dealing with hills for round bails and need to drive up them while using round bailer, you might think about front weights, if you remove the "FEL" or added weights to the FEL.
3pt hitch bail spear can come handy along with round bail spear for FEL. so you can double up on round bails when removing from field. and placing on a trailer or driving to some location for storage.
heavy duty grill guard, for front of tractor. if ya bush hogging.
for bat wing use, easy access to radiator and 1 to 2 hyd oil coolers. so you can blow them out from dust to weed seeds and like. with easy access to air filters.
for FEL work, rear ballest would be needed most likely for max use of FEL, so rear tires loaded, or rear wheel weights, or 3pt hitch ballest box or some other heavy 3pt hitch implement.
pending on use of FEL, if digging, a removable tooth bar. for the front bucket, i say removable. so you can remove and back drag with front bucket.
if going with cab, and using the tractor to move round bails. would make sure you have front work lights, that set high up on the cab. so if you have round bail on front. you can see were you are driving as the sun goes down. due to regular headlights most likely blocked by the round bail.
for the 3 remotes, double check on type of lever/valve you get for each one. for position control to float, to other. so you can adjust things easier.
