The last time I actually released a significant solo project for Newgrounds was in 2013. I still want to contribute something newer at some point, but I keep not remembering ideas and not coming up with ideas that actually fit within my skill range.
Like, sure, I could write plenty of new concepts for what I animate next, but I wouldn't actually be able to animate most of them. My funniest brainwaves for Newgrounds aren't simple enough.
Last time I failed at this was at least 2 years ago, when I tried to animate an ambitiously atmospheric and complex visualization for a Minecraft Volume track, and ultimately gave up. Actually, what finally killed it off was really the realization that Newgrounds would copyright remove it, as there was no way the animation would actually be itself if I used any other music. It had flowing water, leaves rustling on an upset branch, and a lot of camera panning planned out for it - things I didn't actually know how pull off.
But yeah, I know that .swf is not the predominant file format for these anymore. I want to use Flash but unfortunately, you can't bring that stainless vector-based image quality to people now.
Beyond that... maybe I just need to study the art form.