I think that simple planes is an excellent game. It is appropriate for many different age groups. And is a very fun and educational way to learn physics. The skies are literally the limits. I don't really specialize in anything specific, but I enjoy building a variety of things. I have always been interested in machinery, planes, weapons, and just in general building things, making simple planes the perfect game for me.
If you like high-efficiency stealth fighters then you might like the Massacre M-1. Please feel free to let me know what your favorite build style is, and what you would like to see me build in the future. If you would like to see videos from me here's the link to my YouTube channel.