Top of my wish list but saddeningly unattainable at the moment are a set of Heartless wheels- probably a mix of Chasers and another wheel. Heartless wheels are all narrow profile (38mm as opposed to the traditional wider 44mm profile), and having tried some narrow wheels recently I am even more desperate for these. They gave me much more manoeuvrability and agility and made transitions seem that little bit more attainable (I'm slow on getting to grips with this particular technique).
Another reason they seem that little bit more alluring is that during pack drills I am constantly getting tripped up when my wheels lock with other people's. I am not a foot-flailer (I don't think) and I sticky skate as much as possible but it seems nigh on impossible to avoid eventually ending up in some sort of wheel embrace with a packmate. And it is driving me up the wall.
On a lighter not, while trawling the net for anything bemoaning wheel locking, I found this matrix which may be interesting: