I have a small character that I'm trying to rotoscope out of some footage I recorded with OBS in League of Legends. If that all means nothing to you, it's fine, regardless I'm rotoscoping about 15 seconds of footage at 60 fps with the rotoscoping tool. The issue I'm running into is that I'm literally having to go into every frame and correct something because it's not tracking very well with just the software. I assume this is because the background and character are not super distinct from each other.
Also, I've been at it for about 3 or so hours and I'm on frame 126, so I'm 2 seconds and 6 frames in, and I have 1065 strokes. It's starting to slow down my computer and I have a brand new desktop that I built myself for video editing. If it's slowing it down around 2 seconds in, I can't imagine what it'll do at 10 seconds or the full 15. So, I feel like I'm doing something wrong.
Rotoscoping is a slow painful process. I would not use the Roto brush though for your situation, rather masks with splines built on various parts of the character - one for the bulk of the body, and a few others for arms, legs...etc. Much lighter on processing and more effective in your case.
You need to analyze your subject and see what changes shape and/or position in a significant way and what can be grouped together in one shape. Use the least amount possible but balance that out with making sure that what you group together and create one shape for does not require that you add or subtract spline points as you animate the masks.