I'd go electric for a few reasons. The appeal of a gas engine is just to have a gas engine on bicycle, but the reality is I'd rarely use the bike then. I ride for enjoyement, if I have to get somewhere I have multiple other vehicles that will work better than a bicycle with a gas engine on it.
Electric on the other hand is much more "polite". Yes, you CAN make gas engines quiet (I made a living doing just that for about 20 years) but not wihout huge mufflers no one wants on their bike. And electric is so much less fuss. Once the controls are set up there's no screwing with gas or oil or carbs or ignition or any number of other things a gas engine relies on.
If I have an electric bike I can take it on the trails I normally ride and noe one needs to be the wiser that I'm using power assist. If I take a gas powered bike on those trails the natives would gather their pitchforks in a hurry. If I'm on the street there are other gas powered bikes in my garage that woudl get the nod before a bicycle would.
If I wanted a small, gas powered bike to bop around town on, I would have kept this one:
160cc of screaming Italian horsepower. Still no match for the massive land yacht SUVs the soccer mom's were riding around in during their phone conversations. Sold it...