Geez Louise, the complaining in this thread is ridiculous. A fun offseason thought experiment doesn't mean we're going to be tearing down signs and rebranding the facilities. In realy life, Neyland Stadium is a name that shouldn't and probably couldn't be improved upon. Relax. Have fun.
The best stadium nicknames are short, straightforward, intimidating, and to-the-point. The Swamp is in a swampy area, The Big House is big, etc.
I love the wordplay of Volhalla. Maybe something like Vol Holler would be cool, since you get the wordplay AND a little regional flair in it. Then again, it's not really a straightforward nickname like most stadiums have.
The House that Neyland Built is a great nickname. (Fun fact that I learned recently: Gen. Neyland actually began a career as a civil engineer, and also actually worked on part of the structural design of the stadium during one of the big renovations. I'd love to see any other football coach stake a claim like that.) But a nickname doesn't work if it's longer than the stadium's official name.
The General just makes me think of crappy, cheaply animated car insurance commercials.
Being right on a riverfront is a feature that's almost uniquely ours. But "The Riverfront" doesn't exactly strike fear in opponents. It sounds more like a lovely place to sip on sweet tea and enjoy the sunset. Maybe people more creative than myself can come up with an intimidating river-themed nickname.
Rocky Top is hard to beat, since the name is already a big part of the program and announcers already call Neyland that from time to time. Out of all the suggestions so far, that's where I'd cast my vote.