Another thing I don't like about this system is how much it looks like it will get in the way of my ability to multi meld gear for LS mates that previously used said gear until they could afford the next materia to add to it.

Has anything been officially stated about the plan for 2.0's melding request function expanding beyond single melds?

As it was in 1.xx, if you wanted a second+ meld, you had to trade the gear, materia and catalyst to the crafter to meld in their own inventory, then trade again to get the multi melded item back. As an LS crafter, I often spent a few hours in Uldah repairing items and then getting these trades of used gear+materia+catalyst from friends and LS mates. If SE doesn't expand their meld request system beyond single melds, that will no longer be possible with used gear.