I assume the MK bags you do own are in good condition since you have inspected and chosen to keep them? I own three LVs and love them all, but wouldn't sell all of my MK bags for one LV. My MK bags are my every day utilitarian use bags. They serve a distinct purpose in my collection. My LVs have a distinctly different purpose...Galliera (in damier azur is a summer hobo for weekends, travel, and occasional weekdays), Brea (in vernis amarante is a dress up briefcase style bag), Alma (in black epi is a dress up evening bag and can be used during days when I'm dressed up in more formal, mostly black clothing).
I wouldn't suggest selling all your MKs for one LV because you'll lose all the various functionality of your MKs to pick up one functional LV (most likely a Neverfull given how functional it is).