Malets is not a common name. Mallett and Malet are more common and even have a website devoted to them http://www.mallettfamilyhistory.org/. I wonder if it is commoner in Russia - because there is a DJ in Moscow called Natasha Malets (Наташа Малец). Roveren sounds Dutch, and there is a Fort Roveren in The Netherlands. Roveren is also used as a first name in a Simpsons character Roveren Runkeldunk. So neither sound English, but if a character was Dutch then Roveren is better, and Malets if Russian !!

I like rOveren. However, here are some additional considerations. "Rover" is a cliche name for a dog. The second one sounds like "malice" and "mallets," which may be good or bad, depending on your objective.

Both are good but I think the first is better.

As for me, i prefer the second surname.