I looked at compubench 1.5 benchmark (win64, sorry for me) and while some modern cards can composite at 300 fps not so new cards easily can drop down 10x
https://compubench.com/result.jsp?benchmark=compu15d&test=588&text-filter=&o... Looks like AMD Radeon wins at the top, but this is a good chart if comparing to Nvidia boards and how much money you are willing to spend ...
Cinelerra was born more as TV tool, and I guess this explains 'weird' one hit hotkeys.
Probably, but not sure about what are the weird one hit hotkeys. Some may seem weird only because they were added before someone else decided they wanted a different key to represent something and rather than sticking with what was already in use, they changed it. The other 2 articles pointed out by the URLs are interesting from an historical viewpoint and I read the beginnings of both. They include some humor also which makes them very readable but limited time here for reading.