Light(ish)weight Pompetamine

Yes and yes.

That's not what I've read, but do a bit of research and find out how people have got on with tubes in them. If you still don't think they will work for you, Velocity A23 will do, about 80g extra for a pair but also £22 less

I think you were right first time, I just got the wrong end of the stick. Will look into the Iron Cross rims some more. Do you happen to know which of the Hope hubs are disc compatible? Their website isn't helping me a great deal ...