I mainly want an offense that will run from the gun

Id rather see an offense run an actual pro style offense. That can do a little bit of everything. rather have a pocket passer than dual threat

Singleback is preferable to shotgun.

Whoever we get, expect some form of passing offense (shotgun and spread) to be the main focus next year. Consider what you have coming back-
Etling will be a senior, he doesn't have a big arm, but he does read the field well. He could run a spread like Brees did at Purdue.
Before you dismiss Etling's chance at starting next season, consider that Chark is coming back, he's our best WR and likely a future pro, and he and Etling have a rhythm together. I would expect you want to maximize Chark next year, as you transition to whatever you eventually run.

Guice would do well in that type of offense, running draws and a lot of screens and short routes. Since Guice is the other NFL prospect returning, you would expect the offense to focus on those two; going to a new QB in a transitional year would hurt both those guys, and wouldn't get us any more wins.