Wish you the best on upgrades!
There is software to help with online spelling, and while most don't care, it does affect your appearance online, sort of like clothes do at an interview. Since it is a disability for you (rather than the badge of ignorance it is for so many others), overcoming it might be a productive challenge.
Sorry, I don't know how to tell if you'll get a bigger or smaller cabin on 48 except by accessing the FC seats on Delta.com for your particular flight. You could pretend to be buying a ticket for that flight and get current seat occupancy info, although that would not be total sales info. Others might be able to advise on current ways to see how many front cabin seats are still available for sale on that particular flight.
------------------
"It was the epoch of belief, it was the epoch of incredulity..."