I can finally report a successful satellite QSO! Many thanks to all of you for your very useful feedback.
I ended up using my existing 2m/70cm 3el beam on the TV rotator with the addition of an SSB preamp for 70cm.
There are still a couple of limitations with my system. The first being that the antenna is fixed at a 0 degree elevation. I was able to work AO-51 from 7 degrees above the horizon, but lose it around 20 or so degrees elevation. While it's great that I can work it that far out, I'm losing out on the better passes with less path-loss.
The other downside is that even with two transceivers, I'm unable to work full-duplex. The two bands on the antenna use seperate elements and feed points, but share a boom. Transmitting on 2m completely overloads the front-end of the IC-7000. While full duplex would be useful, it's not absolutely necessary.
My primary goal is achieving reliable, repeatable communications (i.e. removing the luck from the equation as much as possible!). Hopefully I'll be able to reproduce yesterday's performance with my exising kit for a little while longer and consider how to add a permanent elevation and slightly longer booms.
Regards,
Scott NW2S