I've been saying for years that Rocket Lounge should be moved to Avalon, it's such a natural fit for that location as there are so many people who want that vibe into the early hours who don't care for anything else in the SE corner, yet have to endure it all to get that fix.
The issue I think is the noise restrictions for that side off the train tracks. I know that The Wheel Of Four Tunes have been bollocked for being too loud at previous late night shows on Sensation Seekers one field over, and have mentioned on more than one occasion that their 3am curfew was pretty strict!