I have 9 YouTube channels. I would say that you have some things right and some things a little off. For instance, posting 3x a week is in the hotspot for YT. However, posting one word keywords will probably get you nowhere because that word can be so many things in so many different contexts. Instead, you want longer strings of keywords that match your content. For instance, if I were to put "metal" on my metal detecting channel as a keyword, I would quickly be knocked down because most people who look up "metal" are not looking up "metal detecting." Keywords like "metal detecting california beach" would be much closer to reality and therefore my video more likely to be clicked because my thumbnail, title, and description match the searched words. Also, thumbnails are the most important thing. Words in a thumbnail are actually scanned by YT's system and can be very helpful in cementing your keywords for the video...there's hours of conversation I could have on tips for starting a YT channel, but I'll leave it at that.