dh- I didn't answer your question about spacing the entire crankset further out from the frame. Since current cranksets don't have the ability to change the BB axle length (as with traditional tapered square BBs can) as you move the RH side outward the LH side moves inward. The LH arm's fit onto the axle can be challenged. The clearances between the LH arm and the LH chainstay can reduce to less then needed. Depending on the shell and bearing's design this ,movement might need spacers behind the RH bearing in the shell. But the LH bearing might not be able to also be moved to the left and the way the axle and bearings fit will be lost. Some cranksets require the LH bearing to sit against a shoulder on the axle for proper assembly. As the rings are moved outward the chainline does too (this being your short term goal) but then when you're in the large cassette cogs (low gears) the chain will then be further off line. You will approach the chain angles that typical cross chaining have. Don't be surprised if the chain drop off issue worsens when using the Low gears and shifting off the big ring.

So as i have tried to explain moving the crankset outward does have it's concerns.

As Francis suggested respacing the rings further apart would be the easiest way to gain chain rub reduction. But then the lever controlled ft der movement might not be enough to keep ft cage/chain rub down. Andy.