It's a significant disadvantage, yes, but I don't see any good alternatives.
Maybe a solution can be found outside the protocol built on top of it rather than force one into it.
An issuing authority, automated or even manual at this stage that swaps BTC 1=1 for a XCP asset called XBTC at a designated public address. I understand trust will be an immediate concern but if initiated by someone of repute within the community (like the counterparty devs) it might just get adopted especially since the protocol supports escrow.
It's strictly not 1=1, rather 1 + 0.0001 BTC = 1 XBTC and 1 XBTC + 0.0001 BTC = 1 BTC.