Meh, I disagree with your theory about using less tags. You should use all 500 characters for optimal results. There is no proof that likes/dislikes does anything to the SEO. I’m sure that is more for the content makers info and viewers warning. The description can be up to 5000 characters. Best to post your other video links. You have no proof of anything, noone does, we can only guess how youtube seo works..
Google PageRank (Google PR) is one of the methods Google uses to determine a page's relevance or importance. Important pages receive a higher PageRank and are more likely to appear at the top of the search results. Google PageRank (PR) is a measure from 0 - 10. Google Pagerank is based on backlinks. The more quality backlinks the higher Google Pagerank. Improving your Google page rank (building QUALITY backlinks ) is very important if you want to improve your search engine rankings.
Keep in mind, this will often mean shifting the focus of your business from more general to more specific products or services. For instance, instead of exclusively offering general home renovation services, you could consider specializing in "one day bathroom renos" or "custom kitchen makeovers." These more specific keyword phrases will likely be much easier to rank for, which will mean you can start ranking that much faster.