The tags are there to give the reader extra meaning about the article. For example, you could tell someone to read an article first in the tag. However, I believe I will offer a way to filter by tags soon. This wasn't their primary purpose, though. They aren't like stack overflow tags. They are more like post-it-notes to guide your readers.
If you don't want to use the auto-generated friendly slug that Silvrback makes for your article, then you would have to edit it to your liking in "advanced post settings." I don't want this to be bloated with features so I don't have a 'slug template' save option. 98% of my users wouldn't need this option. Sorry :)
With thousands of posts the page will be paginated. I'm actually still implementing this. Should be ready soon.
If you do buy a subscription and don't like it, just email me and I will refund you.