I think bucket/grapple lip visibility varries considerably from tractor to tractor and person to person. So sit and see!
So:
An MX size might be perfect and where you end up but I completely understand not being able to justify that expense to yourself and you family. (I couldn't).
But I really think a subcompact will simply not do much of what you want (not just slower) and you may actually break the tractor or yourself in the process.
The largest frame size and especially loader size/capacity in the Kubota B series would probably do a whole lot of what you want without hurting you or itself. I think you'll care more about frame size and loader capacity than HP as long as it's over about 20hp.
Add weight, a quick attach for buckets, and industrial tires and get to work. Put a few hundred hours on it, then sell for 90% of what you paid for it (easy with Kubota/HST conbo arround here), and get your MX size machine if you want/need it.
If you want to look at the smaller L series, make sure the frame size and loader capacities are actually bigger than the largest B (there is some overlap).
All my opinion of course but this it the trajectory I've happily followed.