I'm not sure really. I think more tags would allow the biggest of players to dominate even more tag real estate the way the trending pages work. I personally think that 5 tags is pretty decent. Discovery through tags is still difficult because you need a following and strong voters to get to hot or trending and new is a low quality firehose. I think the comment section is still the best way to find interesting people on here or more niche tags that the big dogs are not so interested in. But discovery remains a huge problem on here. Oh, and there are some nice communities on steemit.chat and discord where one could also start making friends depending on their interests. But it's hard to get noticed really...