I think if Marshall came out with their own version of a Modded 800 that was actually called a "modded" 800, that would do well for them, and I would be interested in Marshall's take on it. Other than that, the market is so saturated with options right now, it's ridiculous (in a good way)
I can't think of much that isn't already available to be totally honest. 50 watt heads in a smaller package like the Splawn Supersport would be great. I dig the small form factor, but need the power to cut in a loud band without the power section mushing out, and most of the lunchbox amps don't deliver there quite yet.