Wow, the big one to my eyes is the 'removeparam=' which allowed uBlock to strip out parameters (e.g. tracking parameters) from the request, allowing you to visit e.g. affiliate links without being tracked as coming from a specific affiliate (if the affiliate info was in the query params at least). Stuff like that is really amazing, I'm glad that here on FireFox we've still got the full uBlock Origin.
I've been trying uBO Lite myself for a few months, and anyone who uses YouTube will absolutely notice that it's worse at blocking. Lite tends to delay playback at the start of a video for as long as the blocked ads would've been, making the site feel slower, and once in a while an ad will slip past the blocker anyway.
I am not so sure if that is the light version. In my (outdated) Ungoogled Chromium which still has classic uBlock, YouTube videos also have delays or do stop playing completely after a few seconds. So I have switched to the FreeTube software to watch YouTube videos. I can recommend that.
It would be nice if uBO automatically got replaced with uBL instead of requiring users to manually install it. A lot of users who might've had uBO installed by someone else won't know how or won't care enough to do it.