New releases are spaced out for a few reasons. New features have to be mapped out carefully (since they interact with each other in so many ways), Alex likes to have as much polish as possible (meaning lots of test-fix-test-fix cycles even after a new feature is mechanically functional, then lots of tweaking to make it look and work well), and, well, he has a lot to do.
The forums are tremendously active now, and he has his hands full replying to e-mails, PMs, helping with purchase problems, discussing feedback -- you guys can imagine, I'm sure!
I definitely understand some of the fear, though. I own Cortex Command. Miner Wars. Project Zomboid. I've seen other promising projects grow, then die, before reaching their potential. Quite a few disappointments have marred the Indy gaming landscape in recent years. It isn't an unreasonable concern.
Alex does the best he can to keep everyone informed of what he's working on (and we all love those blog posts), but he has to divide his time between being a businessman, being a manager, being a programmer, being a game designer, being a PR fellow, and being a marketing exec. It's a tall order.
It's hard to be patient for a game like this. Believe me, I know about that, too.
The donation thing has come up before, and the best solution we have right now is the simplest one: buy another copy of the game, then give it away to a friend, or hold a little contest on a forum or blog and have Starfarer as the prize. Giveaways help the game reach more eyes AND adds some always-needed funding.