The original insight sucked for most people, and Honda lost money on every one they sold. Sure it got great fuel economy, but thanks to its thin tires and minimal weight a small puff of wind knocked it around. Its low-drag rear wheel skirts got ripped off if you didn't detach them before taking it through a car wash. I also was not impressed with its real world MPG of 62 since as you mentioned it was only 10mpg more than a non-exotic-drivetrain CRX HF, which also felt more solid and drove more confidently. And solid-profile rims is another way of saying "Shitty cooling for the brakes," and also doesn't add all that much as far as wind resistance goes - Indy Car experimented with these back in 1988 to see if they could get a few more laps or a few more mph out of them
but dropped them as being too much hassle for the gains. These are guys who get excited if they get one more lap out of some mod. If they dropped such wheels, then they didn't do much for the Insight, either.
Frankly I wish they'd bring the CRX back, in both the HF and the Si form. They're supposedly bringing a CRZ to market in '11, but after looking at the car it would have been better if they hadn't skipped a letter for the acronym.