Your hard work should yield you a financial reward for a great plug-in. It is worth $20.00 however for the most part this community expects things to be free. A better place to start may be putting a donation link on your website, in your installer and in your application. Take a look at arguably the most used plug-in out there (MyMovies). It is still a donation only application. You may want to consider doing something similar to what Andy(DVRMStoolbox developer) does. If you donate to him, you are allowed early access to his applications.
I’m not exactly sure why, but MCML only development doesn’t appear to be a good career choice today. Development in this area should be looked at as a building block for bigger and better things. Slow development down and keep your day job.
There isn’t a plug-in out there that I use that I haven’t donated to. As far as I have been able to see, you don’t have anything like this right now.
Jay Brown