I've based quite a few trips Europe to US around concerts by my favourite singer -last one was a multistop LON BWI PHX YVR LON so I don't see anything wrong with your trip :). It's a great excuse to visit new places and have some fun (and if you can use miles for it or make it a mileage run all the better :) )

I've always found the fan community the best place to get tickets-and I've met some really nice people that way as well as getting better value for tickets than an agency.

Really enjoyed your report and loved your photos -Thanks for a fun and informative trip report.

All the way to Japan for 2 concerts? Sure, why not! AC C/Y
 

Great TR - bummer on the final flight getting cancelled. Very fun to travel for the concert. Btw what happened with GE - did you have to get the card stamped by immigration or were you allowed through? I thought the point of GE kiosk was to avoid the immigration queue!

The GE kiosks are located next to the immigration lines. For some reason they required that an officer at the immigration desk stamp it before I could go to the exit and hand it to the officer there. No idea why. But basically they just take the GE people next, sort of like how checkin agents will take anyone from the F or C line ahead of the people waiting in the general line.