Multisite for Blog Management?

I’m considering WordPress Multisite for managing my blogs and combining content creation tasks. Neither blog shares users or content. Is this a valid reason for Multisite – or can a plugin accomplish the same management tasks?

I’ve tested Multisite with the Domain Mapping plugin and the tld of the child blog (previously separate) redirects to example.com/blog. I believe this would dilute the strength of a tld.

Is there a way to retain the tld in a visitor’s browser address bar (such as example.com) rather than example.com/blog? This question is likely outside the scope of WordPress, but I’ve spent days unsuccessfully Googling for the solution.