Yes the Jetstream is a gorgeous looking bike I agree. Ergon grips are worth the money. On tyres I'd go for Schwalbe Marathon plus if you ride on roads and trails and want almost puncture proof tyres. If not Schwalbe Marathons or Marathon Racers running at much higher psi ratings are excellent. Good puncture protection and low rolling resistance. The Apples are very good tyres but designed for adding some suspension to the ride and you already have that.
The ultimate upgrade for the Jetstream; A Rohloff 14 speed hub. One of the ideal bikes worthwhile adding such expensive mech too! Something for the future
