We've already agreed that we prefer Counterparty to use IXC instead of a metacoin, but without being able to excrow IXC then trading will be slower (taking mulitple confirmations) and betting won't be possible. Plus, it would be very easy for one of the Counterparty assets to become the preferred metacoin over IXC, especially if a Counterparty asset can perform the functions faster.
I still don't understand what's the problem with a metacoin (or an asset becoming the prefered metacoin). Those coins are not new altcoins in the sense that they are independent from IXC. Instead, they are are fully dependent on IXC, but IXC is independent on any Counterparty defined asset/coin. There is no way they can "dilute IXC", only (possibly) add value to IXC (through the increased use of IXC, i.e. transaction fees). Those coins are directly traded with IXC in the network, and since you can not even use those coins/assets without owning some IXC (for fees), it makes little sense even to set up a third party exchange (say for metacoin <-> bitcoin). In other words, those interested in Counterparty features will first need to get some IXC.
Before answering, does anyone know if each Counterparty order, trade or bet is contained in its own separate IXC transaction. Or are multiple Counterparty events crammed into a single IXC transaction? I assume only one event per IXC transaction since we only have 80 bytes in the OP_RETURN.