I really liked RES on reddit and I still miss some of those capabilities like

• tagging good and bad users so that you know them in the future. You could color code them to know instantly if you thought they were bots, trolls, or friends easily.
• to put my favorite subs at the top to go to them instantly
• the multi-subreddit feature
• being able to see between comment threads easily. Right now, the quote bar gets mixed up with the thread bars and there is no separator between them, on RES I could have a thick line if I wanted.

Other than these UI issues, I love Lemmy.