Same. In 2.5 years of maintaining 7 emulators, there probably isn't much of a cavalry coming over the hill to assist.... I would be delighted if people would help out with palettes or really anything at all.
Now don't get me wrong... I've had help. @FluBBa gave me a hand with SN audio. And I've had a few others contribute some graphic elements. I also appreciate all of the testing and positive comments from the usual suspects here. Plus, much of my work is based on giants of the past. But the vast majority of the time it's just a one-man band on these hobby projects. Outside of MAME (which is a bit hard to nail down as each driver/machine is almost a mini-emulator), I think the Stella team has one of the larger community contribution rates (3-4 people who regularly contribute).
Then again, we're developing emulators for a machine which itself is already being emulated and for a very niche group