They have Bitcoin and Voxel (uphold created). If they wanted more profit, they would add ETH and other currencies in due time. Unknown if that's in their plans, so if WAVES can get the not even born atomic trade functionality working, might be a selling point. But right now it's just in the idea stage. How's WAVES going to get this ready , even as a test by summer, if it's dependent on another groups' work?
Gee, look at this..
http://themerkle.com/uphold-will-add-litecoin-and-ethereum-soon/