I try to watch a lot of everything, and love 80s/90s era anime.
My rating system is a little bit of a self-feedback loop, so I reference previous shows I watched to rate new ones a lot. I typically rate a little low, if I rated a show 6 or higher than I probably liked it or at the very least see it's objective quality
10/10 Reserved for Masterpieces + Personal Favorite combinations
9/10 Amazing shows that didn't quite make my all-time favorites list or my favorite shows with obvious flaws usually end up here.
8/10 Good shows that I really enjoyed. If a show is rated this high or higher than you can probably bet that I really liked it.
7/10 - Good shows with obvious flaws or great shows I didn't personally get a lot out of usually get this rating.
6/10 - If I finish a show and think "It was fine." I put it here.
5/10 - A show with no major category in which is excels, simply getting by with being "ok" in every department
4/10 - This is where shows that make me go "that was pretty bad" go. Shows I heavily dislike despite having obvious qualities end up here too.
3/10 - This is where a lot of objectively bad anime fall into for me, if the anime is neither compelling or of good quality
2/10 - Terrible shows that aren't personally offensive enough for a 1/10
1/10 - The opposite of 10/10, a show would need to be horrible quality and make me hate it to end up here.