I looked up all the information you had on your engine. The costs reminded me of the last time I went to the hospital.
Comp Cams recommends 3.73 gears for the cam #35-426-8 you have choosen. But that is assummed it is for a heavier car. That cams power range is 2200-6200 rpms with a duration @ .050 of 236-240, and has a rough idle. Not really a cruising and gas mileage cam that you said you wanted.
You said:
"I like taller gears generally and want good gas mileage for cruising/long trips."
Taller gears and a high duration cam are often times in conflict. This is all about trade offs. My .02 is that the 3.73s are going to keep the revs up for this cam but you most likely will have to start out in second gear as first will be to short. Get some ear plugs to from where the rpms are going be at. On the other hand with the 3.31s you may have some low rpm issues around town since you may not even get in the power range of that cam. If it were me I would go with the 3.55s and one step lower on the cam. I'm a firm believer in building for where you are going to be running most of the time with some left over. My opinion!