2005 Scion xA - Pending Trouble Codes P0441, P0442, P0446 (and rough idle)

The Maintenance Required light flashes on my dash when I start my car so I connected my trusty BlueDriver code reader and captured the above-referenced codes. I checked the gas cap--it's good--and replaced the canister purge valve and vacuum lines going to/from it--no improvement. What should I look at next--the oxygen sensors or...?

Also, I happen to notice that the engine idles a little rough and the acceleration is a little lackluster; it's been that way for a months, now. (The car has around 112,000 miles on it, so it's no spring chicken.) I don't know whether these symptoms have any bearing on the aforementioned codes but it might be useful for troubleshooting.

On a different note...

Have you given any thought to creating a database so users/visitors can look up their car's make/model/year and read all the answers that you've given about it from your website and in your YouTube vids? I'm a database coder, so if you're interested in that idea I'd be delighted to chat with you about it--just send me a phone number I can reach you at (via my contact e-mail addy here) with a day/time of your convenience and I'll give you a ring.

Cheers!