We kicked out Dish Network and couldn't be happier. We have 3 TV's in the house.
I have a mix of 2 ATV2's and 1 ATV3 hooked to the TV's.
We aren't really sports people, so that made it much easier and that seems to be the major snag is sports.
I have my iTunes library on my Win7 PC stored on a 2TB drive. I back that up nightly to an external drive.
On some things including rentals we just use iTunes. If I'm not in the mood for commercials we rent TV shows over iTunes or we use the CW/NBC/ABC apps on our iPad and mirror to the TV. You have to put up with commercials on those though.
As I buy more HD content I can for sure see myself expanding my storage in the future. It'd also be nice to have a dedicated machine that isn't my gaming/everything else PC, but it works for now.