Another Honda hybrid owner!!! Awesome.
I take it you've done all the basic stuff like running LRR tyres and pumping them up good and hard, putting the PROPER oil recomended in the handbook (not neccesarily even what Honda garages will suggest because the real stuff if so hard to find), and making sure the car is in good working order with all brakes not binding etc?
After that just try to learn how to drive the car. Can you get an HCH1 to leanburn? If so you need to maximise the use of that. Use the assist to get you up hills, you gained all that energy for free so make sure you use it. Also keep the car in a gear higher than you'd otherwise think of using. You get lower pumping losses at low rpm and less throttle turbulence with a wider throttle angle so use a high gear and put your foot right down to accelerate, again using assist.
Beyond that you cant run EV only, but you can shut the car off coasting down hills. I only do that if I have 3/4 battery though otherwise I use it to best effect to top up my charge.
The biggest difference you can make is adjusting how YOU drive it. You are doing pretty well anyway by the looks of it so most of what Ive said you will more than likely know/do already!!