I actually had a risk group about 20 years ago that lasted a long time. The only reason it did though, was we played LOTR Risk.
Perform quests and assemble armies to conquer Middle Earth.
boardgamegeek.com
Normally I'm not into this kind of derivative shit, but this game has a few small improvements that make a world of difference. One is that there's a time limit. The ring moves (or has a chance to move) every turn, so there's no more 16 hour long games. The game has an ending, and you score points based upon what you control at the end. Second is the addition of Leaders, who allow you to complete quests to earn additional armies. For example, ending with your leader in a certain territory might give you extra armies in that territory, or anywhere on the board, and also earns you points
Third is the cards have set turn in values based upon the icons on the cards...no more turning in the first set and getting fucked with 4 armies while a few turns later a dude turns in a set for 20 and it just keeps getting more and more ridiculous. Archers are 4 armies, horseman were 6, eagles were 8 and wild is 10 if I recall, and it caps there. So far less huge power swings at the end of the game.
It makes Risk a game you can actually play with non autists, still has some strategy, and never devolves to one person just sitting in one area the whole game (hi2u Australia) and stockpiling shit, because you won't be able to stockpile shit effectively, and you can't earn points from leader quests by turtling up.
Plus, it's just a cooler map.