I wouldn't be too discouraged about your current mpg. First, it really is pretty good( the TCH should get close to the HCH2 according to CR and a moto mag that did testing in CA); Second, Honda owners have set the bar very high with their 47 mpg average here.
No matter what the Honda owners say, it isn't easy to average 47 mpg with a HCH2! They-forum members- are extremely committed-and use all the tricks you see here.Your mpg will improve as you get more adept.
Luck.Charlie