Interstate driving isn't as enjoyable to me, except for the on ramps you mention <grin>. I haven't done too much of it, from what I recall 80 is pretty smooth, 85-90 there are some shakes (not sure if it's me or the car haha). When I am cruising I try to head toward rural areas like you, curvy roads or ones with elevation differences are my favorite. On those rural roads there is generally less traffic and opportunities to pass slow moving haulers. That is when I let the turbo sing. Generally speaking from a light I don't 'get on it' either. If someone flashes me a thumbs up I will give it a little extra to give them a grin, but usually under 5psi on the boost. I do love that turbo whistle though.
I do think our cars ride like no other and I drive mine any time the weather allows.
Along the same topic of this thread I recently learned, after blowing out my second gear, that driving with higher boost should be reserved only for WoT. I thought I was 'babying' my car by never opening her up 100% It turns out, that while i might have been babying my engine, without WoT the transmission valve train doesn't open up fully, and it puts a very hard strain on it. My car runs 18psi, but I would go 3/4 throttle and do some 12-15 for passing. So I was beating on my trans. Not sure if anyone else heard that, but figured I would share.