I think first create only local version, it will take a while to create good web gui.
Yes, in some cases i can agree with you, but i think that we can split work between some guys, one part of them will work on CLI / GUI, and another team will focus on WEB interface.
Maybe gui should be auto generate from onebash, if fullzero change something (add new miner or currency) in onebash it will auto change on gui (less work for future).