I think it's great that you're sharing this to the community despite the other alternatives. It would be pretty to have a selective palette changer to further modify the parts like what Sharm says. Keep rocking! I can't wait to see what game you're trying to make.
On the subject of ruby gems and plugin manager, the screenshot shows a single window to display the plugin's parameters. It doesn't make sense for them to show that if we were allowed to integrate plugins that modifies the default editor.
Good lord this is taking forever, I'm not even out of the opening really and I've still got hours worth of work to do before I get to the main gameplay loop. Orphan of Time will probably be done some time next year, If I'm lucky.