So I guess you don't have Gmail's recipient autocompletion, or you do? This is the killer feature of Gmail for me, with its keyboard shorcuts and search.
I don't need to search. My inbox (my only folder) is 4 items at the moment. I rarely initiate an email conversation but whe I do it's simply select the addres from the text file and paste with the right mouse button.
Mutt has an autocomplete function but TBH I can't be bothered to set it up.