I also switched away from Apple Wireless routers and have had fewer issues since.
Interesting. But "it just works"!
I've also had problems with getting my printer to consistently work on the network (via ethernet). It'll work just fine and then nope. Wonder if it's all related.
In the past, a simple reboot has often worked with ATV problems, but it wasn't helping yesterday.
Strangely, my wife pointed out that our recent ATV problems have coincided with me leaving the house with my laptop, which is ordinarily connected via cord to the router and also wifi for Airdrop purposes. Last night, after I tinkered with the ATV for a while, including manually assigning it an IP address, I again took my MBP off ethernet, then switched one other thing (which had already been tried to no avail) on the ATV, and it worked again. The causality, if there is one, would be inexplicable, but then again so is the fact that this just cuts in and out at random. Last night, though, although it got back on the internet, it had trouble maintaining a connection for a bit, even on the local network (as confirmed by its inability to even play music from the computer without interruption). Well, at least a factory restore may be now back on the table.
Matt, what router do you have?