Standing for mounting is fixable, actually not all that difficult. My horse went from bolting to snoozing at the block within a week.
The bigger question is Do you really want a case of the "If Only"? If only I had lost 50lbs, if only I had more $$$ for training, if only.....
Horses don't gain value standing around mowing pastures.
I'd say sell 'em all and go buy a well-trained, safe, sound, broke horse that you can ride TODAY. Give yourself some time to really enjoy your riding and if you want a challenge, consider adding a greenie then.