My
B7800 was the first tractor I bought. 40 acres. [NOTE: sometimes when one makes a big property purchase there's not enough money to but bigger tractors] I've put it through heck and back, over 1,100 of the toughest hours that any tractor has likely seen (again, refer to the fact that I have 40 acres). I really didn't know any better; that and when I have to get something done I get it DONE! Anyway, 1/4-inching valve for the 3pt suck, as do the lack of any stabilization for the lower arms (this can be rectified with buying and installing different arms, I believe- that or adding on something- never got around to doing this). While you/OP didn't land one I still wouldn't discount getting one should another pop up.
Weight isn't a big requirement unless one needs a lot of power. Ballasted rears on my
B7800 make it work well, enough to stabilize it (and allow me to pick up max weight on the loader w/o problems). If you have soft ground you're going to find that a lot of weight is going to do a LOT of damage: I've spent plenty of time smoothing out ruts from log skidders. My two favorite combined words: It Depends. No real heavy work with my larger, heavier tractor when the water tables are high: I can use it around the house, handling feed and moving firewood up to the house, but that's about it. Anywhere else if I have to run something it will be my UTV (which, of course, ain't a tractor) or my
B7800. I've moved plenty of stuff with my
B7800 that I couldn't lift: one gets creative. I've moved around stuff that's thousands of pounds, pushed/spun around IN MUD (some clearing work). Small tractors can do
almost all the same work that a larger one can but they do it more slowly.
That said (and because the 1/4-inching valve sucks so bad- I can operate it without thinking, but it's a constant activity, which can tire a person out [though much of the time the tiring is only noticed when you stop]) I'd recommend an L-series around the 30hp range. One either figure out exactly how much weight and what kind of work one is going to be doing (you wouldn't guess about what kind of car you would get without thinking how it was going to be used!), or guess and hope: even if you THINK you know what you're going to be doing there's a good chance that that will change. You can better put your mind at ease by understanding that if your not stuck with something you buy, that you can sell and buy something else.
No matter how big of a tractor one would get you'll still find things that it's not powerful enough to do. You can almost always just go rent more MORE power!