I'm guessing a 2 lb savings in total kit wouldnt be enough to switch out all the gear. Heck since wife is bringing OMD, an ultrawide for that camera would be a compromise, where the 7D would have the 55-250 married to the camera.
Well first of all one has to accept smaller and lighter =/= cheaper.
I live in Australia and I usually have to settle for grey import. Just checked the Oly 9-18mm on eBay and it's cheaper than 10-22mm ($600 vs $700 AUD).
Sure you can argue that the 10-22 is slightly better/sharper, but DR wise Oly can easily match Canon sensor, and Fuji/Sony totally trumps any Canon.
Basically you aren't really losing anything IQ wise, and getting the same performance (if not better) in a tiny package.