I think the big fish Brad will be shooting for is a decent player who is an analytics darling like a Trey Murphy or something. Plus a half decent player in the trade to make salaries work.
I would be very surprised if we get an all star or former MVP back. Management clearly believes in Tatum and it seems like whoever we get will be meant to complement him. Management also clearly believes in depth so I do not think they will go the route of another max-ish player.
I would think this means in terms of roster, the team wants a big defensive center (like a Mitchell Robinson), a change-of-pace microwave scorer (like a Pritchard), and a lockdown 3D who can take on the tough matchups. Very Nowitzki-like in terms of roster construction when I look at it