Funnily, I think they would have had an easier time adapting 4e due to how 4e combat was constructed (and with that though I will lament that I won't get to the crazy summoning shenanigans I get in my 4e game...)
This! Well I plan on messing around see if I can get some 4e features into the game when it goes live with the editor. Get some use out of my old books.
If they chose to do a 5e/4e blend that would have been well received. Even though 4e wasn't as popular as other editions, it still had some great ideas.
My players have always enjoyed 4e inspired homebrew.
