Kudos! Welcome to the Kubota experience. I can't imagine that there's a better small tractor for the rural lifestyle--I've had an
L2250 for 20 years now and as people have said, can't imagine living out here without one.
Definitely get hooks welded onto the bucket, along with some sort of reinforcing bar. I use them constantly for stuff like:
1. Want to put my generator away but don't want to roll it across my pasture to the storage building. Pick it up with straps attached to the FEL and carry it slowly from the bucket.
2. Bought a 600 lb joiner from Grizzly; lifted the table off the back of the truck and set it down on the base, again with the FEL and straps.
3. When I'm doing firewood, if I can get a chain around one end of a log I can lift the end, stick something under the log, then relax it. Now I've got a piece of log off the ground and ready to be cut into rounds for firewood without having to worry about rolling the log to complete the cut or touching the ground with my chainsaw.
4. My wife will ask me to remove a shrub,so I'll wrap a chain around the base of the shrub and wiggle it loose with the FEL then yank it out, carry it to the "dump" and get rid of it.
5. ditto fence posts: I'll wiggle them back and forth with the FEL, then lift with a chain wrapped around the post.
IN ALL CASES YOU HAVE TO BE SUPER CAREFUL NOT TO UNBALANCE THE TRACTOR. Just like when using a tablesaw you have to be super careful not to stick your hand in the blade

The trick with the FEL is to go really slowly when you're applying pressure to see how the tractor feels. If it starts to lift or tip at all, even a few inches before you've got full weight on you need to back off immediately. Even with a counterweight on the 3PH you can get real tippy.
TRACTORS CAN KILL YOU. Keeping that in mind, all the time, is a helpful attitude.
Ok, soapbox stored away.
So useful attachments, tricks etc:
anything you can do to make it easier to hitch up 3PH implements will help your life. I don't have a quick hitch and changing implements is a PITA.
a rear work light (you could buy something for $12 from PepBoys and wire it yourself) can be a big help.
I wish I had a place on my 2250 to hold a few tools, ditto a logging chain.
Stuff I use most: FEL and box scraper. In the spring my vertical 3PH log splitter is on for a month or two until I get all my wood done.
Box scraper is super handy, especially with a top n tilt. My neighbor has one that I've used and I pretty much don't use mine anymore but borrow his setup when I've got dirt work to do.
I've got a rear blade that I use for pushing snow. It's light and of limited use. the snow if it's heavy will jam between the blade and the rear tires.
Chain harrow: got this and found it won't work if you've got weeds/grass where you're dragging. Dragged our community road (got lots of thumbs ups from the neighbors) but it wore the teeth down on the harrow so quickly I stopped using it for gravel.
Bush hog: before I had sheep I used this to keep our pasture mowed. Very helpful with blackberries and small saplings--big ones just got bent over.
Next thing on my list is a 3PH setup to hold a trailer ball, so I can move equipment trailers around without the hassle of hooking them up to a truck.