If they are going to bring back Hank then it will probably be six months before Ant-Man 3 since they usually start publishing more content with movie characters near to when they have a movie coming up (like Morbius for example).

I would like to see Hank back as either scientific adventurer Hank or Giant-Man. Raz can take up a new identity since I don't think there is any great attachment to the Giant-Man identity for the character.

Hopefully when/if Hank comes back writers do something new/interesting with the character. I'm a bit bored of the same old new identity, Janet relationship drama, Ultron conflict and depression story cycles we have seen many times before.