re: What router should I buy?

I'll add those in, but you're right that most routers prioritize traffic pretty well. I've tested some of the network prioritization options on a few routers and never saw any significant difference. Routers pretty well know that when two devices are suddenly demanding a burst of uninterrupted up and down stream bandwidth respectively, those devices are the priority at the moment.

Thought about covering DD-WRT flashing, but I think that's targeting people who don't really need a guide.