There is the old social media user type "pyramid" of 90% just lurking, 9% commenting and interacting, and only 1% of users being active posters themselves (iirc the numbers correctly). So by that logic, any OC is the most "valuable" since the least people post it. Ultimately anything beyond just passive lurking is very valuable.
Personally I mostly comment on things, which is generally either my opinion or the first dumb thing coming to mind. Works well either way for conversation or just entertainment.
When I make posts I tend to only make some when I have a question or need help/input on something. Churning out memes is not up my alley I suppose.
TLDR: Just post and/or comment whatever you want. Valuable either way