Hi John
I also got a new 650 last year, now done just over 8500 miles, trip meter shows 70 mpg, didn't start off that high but increased as the engine got run in. I ride fairly quickly but I'm no knee down racer, too old for that sh!t.
I also found the throttle a bit snatchy to start with but I put it down to the change between my previous bike (carburettors) and the glee (injection), you'll get use to it.
Haven't had a problem with the bar position but I know lots on here have used the risers, I'm sure they will comment in due course, they are a very friendly bunch with lots of great info.
Had the engine cowl and centre stand fitted from new both work great and seem to be a must have on here.
Enjoy the bike, you should have great fun on it, if my experience is anything to go by, still can't believe what a great around bike I found, corners well, plenty fast enough, economical and doesn't go through tyres in a few thousand miles.