I can go either way on this one, but I would share my brief experience as chair of the status of women committee, where we did go ahead and create a subcommittee and we did have a meeting. What we found was that when we brought it back to be ratified, there was a disagreement on support of the steering committee anyway, so we ended up deciding that it just put in an extra step, because we wanted to have the full discussion.
The other thing is that I don't think there is anything that precludes you in the future from appointing a subcommittee if you decide you need one. That's something to keep in mind as well.