Contrary to common wisdom, the best hypermilers generally
avoid "EV mode" to get maximum mileage. Many new hybrid owners tend to over-use it.
First thing I'd do is figure out how to get the engine to stop running when in motion and it's not needed, then maximize the amount of time it's off. I'm not familiar with the Insight 2, but the Prius' engine stops running when you release the accelerator under most conditions (once warmed up).
The 1st gen Insight's engine only stopped when the car was nearly stopped (coming to a stop). Not sure if the Civic hybrid worked the same way.
Are you familiar with pulse & glide? You can often modify that technique for sub/urban driving and get great results without appearing to be doing anything "weird" to other drivers or your passengers. It's actually OK to get relatively crappy instantaneous mileage while accelerating, provided you average it out with infinite mileage in a glide that's long enough to make the math work.
See: