Yes, if it supports --card-edit it would help a lot.

I was actually surprised to find out this doesn't already work...

I would like to be able to have two or more GnuPG cards inserted at the same
time, and have gnupg/gpg-agent/scdaemon notice all of them and use whichever one
was appropriate for the operation at hand, without my having to switch them in
and out.

My personal application for this is that I have a personal key and a work key,
and I want to be able to sign with either of them without having to swap
hardware around. It's pretty easy to set up all the other parts of this to be
seamless with Thunderbird/Enigmail/gnupg2... it works fine until you move the
keys to cards, at which point gnupg's inability to automatically choose the card
it needs really shows up.

In an ideal world, this would also work with gpg-agent as a backend for ssh.