this is a forum mostly of sub & compact utility tractors. i have always been impressed just how many owners push their equipment to the max, sometimes over, in trying to extend their machine's capacity.
assume you're considering a 3ph 6' rather than drag type. if you go the 6' route, just be prepared to go slower & do frequent blade sharpening. keep an eye on the temp gauge as well & take care on slopes...In addition, would not recommend going a lighter duty on 6' to save weight.
good luck with your decision, let us know how it goes. respectfully,