But not miles from MileagePlan Dining either?

Ie, you're calling attention to yourself by not earning miles any other way than through CC signup bonuses. Why not do at least some of that minimum spend eating at MilagePlan Dining restaurants? Then your AS account won't look as if it's all credit card spend and nothing else (each such dine will post separately, so a handful of such dines for each card you churn will make you have more earning posts from dines than from the card itself!).

And/or anything else to give your AS account some "diversity".