There's a reason why Kubota is so popular. The
L2501 will surprise you with what it can do....but mostly you are going to be surpised how comfortable any new tractors are to run compared with their predecessors. Tractors really have become a "low to no maintenance", "grab it and use it" kind of tool.
Sounds like you have reasonable expectations.
If you don't mind a few questions, How do you feel about manual shift? Does it have to be new? Does it bother you that since 2014, anything larger than the 25hp tractors prefer or even require to be run at higer RPM instead of just idling around...? BTW, you are going to love the 4wd & power steering...
Back to the transmission question, most people today like HST transmissions and foot treadle control, but the
L2501 you mentioned is manual like the Massey. You may not know that many manufacturers also offer the glideshift/shuttle shift optional transmission that has column shift and fingertip controls instead of so much foot work. Less $$ & saves a few HP over HST, too.
We've had horses a long time and tractors too. If I was doing what you are - and was concerned with budget - I'd take a checkbook down to your favorite local Kubota dealer and tell him you are looking for a recent trade in. It should be an immaculate pre-2014 kubota in the L or M models in the 30 to 48 hp range. Bs are a litte to light for your work. It needs to have a loader and a 60 day warranty and less than 800 hours. You will consider other transmissions than HST. All of these except the transmission are premium features, so he will ask too much...but you'll have the last laugh.
Still at the dealer, ask your wife for a sanity check, and drive it to buy it on the spot. If anything at all bothers you about the deal, pivot to looking at new ones.
There will always be new tractors available, and it appears that other than in California, there will always a solid market for the pre-2014 models as well.
Luck,
rScotty