I'm with you. The Overflag, while awesome, is really just an improved Flag. I mean, I could be wrong, but the only real difference is its improved stats? Well, that and its head module.
The Shell Flag, on the other hand, really looks like someone took the time to consider what role it would play. I mean, yeah, it's really just a Flag with a pretty new dress to wear to prom, but I think that's part of what makes it so neat. It's a Flag, but it's still a new beast entirely. Plus, I think it's safe to say, the Alex's chobham armor was awesome as hell and this seems to be along the same lines.
Out of curiosity, is there any other suit that's known to use nanomachines in the series? I can't think of any, but I don't have to same encyclopedic knowledge that some of you guys have.
On an a purely fanboy perspective, I look forward to seeing the Shell Flag start pounding on Tieren Ground Type.
Sorry to those who prefer to Tieren...