I do not think they need to be attractive. They are very functional. That said. You could turn off the electricity to that area, unscrew the brass plate covers & paint them with a metal paint which will match your flooring.

If it's not too late, you can try googling for what you need. For example, if you want unfinished maple that you can stain to match the floor, google "unfinished maple outlet covers." This company offers both unfinished and finished covers.

http://www.bairdbrothers.com/Maple-Receptacle-Cover-Plate-SP1000-P1357.aspx