I'm the only current complete seed for a torrent that is reporting 1.928 Available Copies

I have it set to Super Seeding, which will hopefully give priority to the rarest pieces. I assume that this would be the 0.072% that is lacking to make 2.000 Available Copies at which point If I stop seeding, there is theoretically still a full copy shared among the remaining peers.

So could I logically expect that all my uploads for this torrent will be of the missing pieces?

You are correct in your assumption.  You can verify by watching the HAVE messages that you send out when super seeding.

HAVE makes sure you only send out a block 1x, until it is seen on the network, you will not send another block to that same peer.
This is useful in your situation to provide the least upload for creating another seed.