Retraining him to the crate is always a good idea. What if something happened that truely required a crate and he hated the crate? You would be stuck. Better to move in a positive direction and smooth everything out. Being gone 6-7 hours isn't as bad as 8-10 but it still more than he is used to.
So do what you are doing and make the crate a happy pace again. Yes, feeding him in there is fine. Try not to leave him all day with a bowl of food - only use it as a place to eat but be sure to let him out to soil afterwards.
Letting him have the run of the house isn't 'winning' for him. It's not like demanding that you play, or demanding that you feed him. It's just failure to teach him how to be alone in the basement or the crate.
I think I like the gate (one thats screwed into the wall so he can't push it over) idea better than the door only because it still allows him to see whats going on. The door might be fine but he might scratch at it a lot when he hears noises and he can't see what's going on.
Love Them & Lead Them,
~Elizabeth & Doug
Dog Training the Way Nature Intended