I haven't got any knowledge in modelling, so I will use what the editor gives me. For the dead protoss bodies i Was thinking in using the models of the preservers in the Zeratul's mission of WOL. I have made a sketch of the map in the editor (see below).
I can't think in a way to cross the roads between the 2 stories. If you figure out how to, we can link both campaigns and make them more complete and interesting.
I would appreciate if you help me, and I would be glad if I can help you too. But I'm in America and you're in Europe, so we'll have to wait until Blizzard join the servers. Anyway, I'm still not working in that Cavern mission, and that Blizzard update seems to be close.
EDIT: I need to repair a warpgate in the game, maybe your hero could help me to do that.