It's going to be interesting to see what they trot out with. Wade was in the press a couple days ago saying the starting PG job is "Chalmers' to lose" so at this stage I'd say it's a bit too early to call.
I personally think they would be best having Miller come off the bench to lead the second unit, as there's not a lot of wing / guard depth currently and he can also create shots for others. Chalmers would also be their best option to defend the quicker points in the league (Rose, Rondo, Paul, Nash, Parker etc) to save Wade's legs for offence, at least to start games.
One thing is clear though, they have plenty of options. They could go big (Z-Bosh-James-Miller-Wade), small (Bosh-James-Miller-Wade-Chalmers), defensive (Z-Haslem-James-Wade-Chalmers), 3-point (James-Jones-Miller-Wade-Chalmers), crunch-time (Bosh-James-Miller-Jones-Wade).
I really like that 3-point line-up, running a P&R with Wade & James and having Jones, Miller & Chalmers spotting up. Wouldn't be able to play them more than a few minutes due to the defensive issues but would be fun a couple of times a game to see!