many times I try to find new series based on elements that I liked in other manga,

I think it would be good to have search in Description, for example: searching the word "Basketball" will show the series "Power!" in the result list.

if search in Description is impossible (takes too long maybe...) then maybe a Tag (keyword) system is a good option.

I usually like long series so it'll be nice to add filter like min/max volumes.
meaning "show only series with at least/most X volumes"