Your best bet at making your Ideamarket NFTs valuable is by getting famous people to rate them. If you don't know a lot of famous people (we sure don't), your best bet is attracting citations, so that your post becomes a default reference point for that topic. (Then, famous people will end up rating it anyway!)
Tips:
Write in complete sentences. A complete sentence provides context and expresses a point of view, rather than just saying alien video https://youtube.com/9jf209mm2me....
Limit each post to 1 main idea. If a post has multiple ideas in it, it will be less useful as a citation because people might only want to cite half of your post, and won't be able to.
If your post contains a link, provide context. Summarize the link so people know what it's about without having to click it.
For more examples of what a good post looks like, see the arguments posted on Kialo.com.