One of the main advantages of optical wireless flash control systems is that they don't require anything extra: at least with many cameras, they work with the built-in flash, and can often control (with TTL, even) slave flashes with no added adapters. Olympus has such a system, and it allows one to have multiple flash groups and adjust their power from the camera body.
However, the Olympus O-MD E-M5 has no built-in flash. It comes with a very compact clip-on / hotshoe unit, the FL-LM2, and this can act as a wireless controller.
Having to carry a little clip-on thing negates that main advantage, though, so I was wondering if there are any solutions which work with Olypus which allow power levels to be set from the camera body itself (presumably, from the radio controller unit).
I don't need TTL (although that'd be nice). I just want to be able to take test shots, check, and adjust power until I'm happy, without having to go around to each flash manually. (Getting assistants to yell at would be an alternative, I suppose, but it's not practical for everyone.)
PocketWizard appears to have some products that will do what I want, but as I understand it, these require a system-dedicated controller, and Nikon and Canon are the only options. Is there something I could do for Olympus, or is optical wireless my best bet?