Well, the work thing depends on what type of work you want. They are adding a technical area, like an industrial park, but this will be geared toward tech jobs. I forgot who is going to be the first in it. Maryville is growing. They have a mall, Target, SuperWalmart, Home Depot, Lowes, and more. Most any other store you would need is not far down Pellissippi Parkway (I think it is listed as 140 on a map- I'm not sure if it is officially an interstate, but it is like one). There are many restaurants and they keeping adding more.
Check out the Maryville paper at :
www.thedailytimes.com
They have jobs, houses, and you can see in general what is going on.
I'm not really sure about housing, but I know in Knoxville headed to Maryville on Maryville Pk the newer homes do not have much land. You know in those cookie cutter subdivisions. If you look around, you can probably find a house that isn't too old that has some land.
There are several parks in Maryville, but as far as I know the only off the leash dog park is in Knoxville. It is also close to the Smoky MT National Park which has trails and areas you could take the dog on the leash. Here is the link to Maryville/Blount Co. parks:
http://www.parksrec.com/
A work commute between Maryville and Knoxville would depend on what part of town you were going. Downtown should take 20-30 minutes. West would probably be about the same, but traffic is bad on that side of town. In my family, there have been 4 people work at Alcoa and live in South Knoxville. It takes about 20 minutes. My dad was on of those. Like if he worked 6-2, he would be home at 2:20. By 2:30, it's time to worry because it rarely took any longer than 20 minutes.
To me, Maryville and Alcoa are basically the same place. I'm sure living there you know where each one is, but just visiting you don't really know the difference. It's like one side of the street is Alcoa and the other side of the street is Maryville. Rockford isn't much of anything. It's just a little spot where there is a name change between Knoxville and Maryville as you go down Maryville PK.
Hope that helps a little. If you narrow down the work field for us, we might can help you decide which is better Maryville or Knoxville.