RE: giving electric a go
I get 10 minutes plus on my Galaxy, Tristania. They are SMALLER then the one you are looking at. They use a 480 2s battery ans weigh in at about 6 ounces ready to fly. Mine are about 1 1/2 ounces over weight but fly very well. They do not like a lot of wind. That is the down side to the lite weigh planes.
It is a balance between flight time and weight. Bigger batteries mean more flight time yet they weigh more so you use more throttle.
Maybe look for a liter weight plane to get longer flight times?
Buzz.