This answer will be from an online perspective, fwiw.
First, some general thoughts:
Basically, only thinking players (i.e. regulars) will consider what your range is and make their decisions based on it. How deeply they think about your range and how accurately they can hand read will vary a lot from regular to regular. Fish will almost never hand read or figure out what your range is.
On the other hand, your image is much more transparent. If you're raising every hand, even the most clueless fish can pick up on that. A fish might even overreact to such a thing whereas a reg will understand that you're probably just getting a decent run of cards or are isolating a really big fish or something.
Onto the specifics:
TAG 3bet range: Lots of TAGs will 3bet all sorts of junk and a standard value range like JJ+/AQ (is this 6max? That range is tighter for Full Ring, fwiw). 3betting junk is fine vs you, assuming that you fold to 3bets a reasonable percentage of the time. One problem is that the fish can be spewy enough to overcall the 3bets so this can make for a huge problem for the TAG occasionally (fwiw for the TAG this is a huge problem for him OOP and a small one IP). I'd personally 3bet lots of weak Ax and Kx suited hands for their blockers and ability to flop something decent post. This of course adjusts based on how often you call/fold/4bet.
I'm tighter than most here but I'd call with lots of broadway type hands. OOP, unless we're really deep with the fish, I'm not looking to call with lots of SC type hands.
If you had opened instead of isolated, the ranges above would be tighter. Your range is looser because you're isolating, so the TAG can loosen his range vs you because your range is weaker than when you open.
Most TAGs will be aware of this dynamic but if the TAG is getting more involved by 3betting/flatting your iso more often than he would versus a standard open, he's aware of the situation.