Thank you

We estimate it should be 2-4 weeks to implement most of this stuff (except for complex auto-trust, just normal trust + payed trust).

Best 1000 - 2000 BTC to do it really.
More to do all the fancy/paranoid ideas as well. This messages will be carrying most USD/KiB worht so make sense to super-secure it, but perhaps later in next iteration/bounty.