We are looking in the Help Guides for any guidance and / or good practices on handling links and tags. 

The ability for Members to exploit these to benefit their external websites is something we like to avoid unless this practice, by itself, would be a turn-off to our Members.

Outbound links get the rel=nofollow attribute added, so users get little to no benefit backlinking to their sites or anything like that.

For tags, you can set up a closed system where you predefine the tags in advance and those are the only choices you can use.  

I would highly recommend this over open tags, which becomes a free for all.  Even my well meaning users tend to get tag-spammy when they freely create tags.  

You can also use Advanced Tags and Prefixes by @Kevin CarwileCarwile in the Marketplace which adds more functions like colors and Prefixes.  

Two great and very helpful responses. Thank you, Gentlemen!