I personally think that most people buy tractors that are too big for their needs and you are definately aiming toward falling into that category. I think it might be tempting to buy a bigger framed machine so that you can use those "free" implements but it seems to me the free implements actually come at quite a heafty price.
You have some short term landscape work to do, then you need to mow a couple acres. Your neighbor needs you to buy a FEL so he can get one for free.
Gatorboy has given you some very good advice.
If it was me, the largest tractor I would look at is a small frame CUT. You can pick the brand there are plenty of good units out there, in the 21 hp range the CK20 is probably the best, but if you want to pull a 5' bush hog, then it will likely be too low in power. I just question if you need to even use that 5' hog.
Why not just rent a unit in the spring for a week, line up your big chores and take a vacation week. Hog that field one time (an hour or so worth of work) then go after building your landscaping the remaing time you have that tractor rented.
After you are done, you won't ever need the disk or bush hog again. You may be able to get by without a FEL as well. That would leave you with the Toro unit you already own, and it would save you about $12,000 to $15,000 too!
Now if you really want to spend your money, then take a look at a large H.D. garden tractor, it will take a 60" mower deck, it will keep that field that you just hogged looking as close to a lawn as it is going to look. And you'd still have money left over. I guess the biggest thing I would consider would be the Cub Cadet 5000 series, but a Cub 3000 series would do what you NEED done, without wasting your hard earned money. A nice John Deere 300 or mabye 400 series garden tractor would also do the job. JD and Cub build garden tractors that will last you 20 years.
A good garden tractor won't give you the testosterone high that a big tractor will, but on the other hand it won't cost you as much, it won't be too large to fit under the trees you are about to plant, and while it won't make your neighbor happy, it won't be a waste of money either. I'd seriously reconsider your choices, and I'd seriously consider renting a machine for a week or two and then using a garden tractor to do what you really need done after that.
It is nice that you are willing to BH your neighbors lots, and do all that other stuff, but what if they move? Or you don't get along at some point in the future? And will they pay for upkeep on your machine? And if the neighbor uses the machine to do some FEL work is he paying for any damage? Or the oil change? You sound like you are going to be paying for this for a long time, I think you seriously need to rethink this purchase. Just my 2 bits.
But it is easy for us to tell you to go buy a tractor, sometimes the hard part is facing the reality that the advice we are giving is not in your long term best interest.