Welcome to the forum! I got the 3901 and am doing the same chores/work/playing you are talking about doing. I just rolled over 70 hours and here is what I know... this is not yours or my grandfather's tractor! The 3901 is light comparetively speaking to a 35-40 HP from back in the day. This is good and bad. I too have a 1/2 ton pickup and did not want to buy 3/4 ton truck along with a tractor... it would be nice though! I have a 20 foot trailer and 1/2 ton pulls it and stops it, no problem. Get trailer brakes, though. You may need to stop in a hurry and it is probablly not good on your truck's brakes stopping truck, trailer, tractor, loader, bucket, implement, etc...
I am going to advocate for the 3901 because an accomplice is nice to have
! Most everyone will tell you that there tractor is the right one for you!
The 3901 is a great tractor and it will do what you need as far as the food plots and light brush clearing. If you mean bulldozing when you say "working up new food plots" you may need to step up in size or two or three! It is a tier 4 and noone knows what future problems are to come with this technology; time will tell! I have the HST and love it but others swear by DT or shuttle. I got R1 tires loaded because it gets soggy here. I got my tires widened for a better stance and I feel more comfortable on a wider footprint. I have replaced the damper rod on the HST (backed over a limb just big enough to jam in the bracket and bent it) and both tie rods
Both aggrivating and both probably preventable if I bought it to keep in the garage!
I would suggest you test drive the 3300, 3901, 4600, 4701 and see which one feels right. Good luck in your search!