I don't really see a heavy wallet being used all that much - it requires both bitcoin-d/qt and counterpartyd, most people that want use 25gb worth of harddrive space and run a full node are capable of installing a command line client. A lightweight local-only desktop wallet would see a lot more use I would think.
Right, and those who need it pry are ones who can talk to counterpartyd with cmd line. I run counterpartyd myself, only because i hold xcp since the burn. And the way I use xcp is by sending them to counterwallet, once in a while. So i only need to know how to send xcp by cmdline.