During the Cloud and Tifa mission you still need Tifa in the character slot 1 position. I don't mind it because it is not an inconvenience to put her there. It is no big deal. The music fixes work great, though!
EDIT: There is a glitch where Tifa only learns spells from items if she is in the top character position. It is just a small thing. Nothing to worry about.
Need her in slot 1 for what? I'm sorry if you've mentioned this one before but I can't recall anything about It. My memory is bad...
EDIT: Ahh yes, did a bit of backtracking threads here and I do remember:
"During the Cloud and Tifa mission, if Tifa is not in the first character position, she does not learn spells from items. "
Hopefully this one has been fixed also with this soon-to-be-out-already v1.7.4 update - I was able to track down the problematic code with the items that teach magic doing weird shit and fixed/reverted it back to working. It was a patch that's been in this hack since 2010! So yeah, I'll test this here now actually and hope for the best.