Before the Airtrain, they used to run a Q10a bus from Kew Gardens NON-STOP to JFK [in the morning rush hour in the JFK direction only].
There is a Q53 (with fewer pax than either of the airport routes) which runs NON-STOP (LTD version) from Jackson Heights to the Jamaica Wildlife Refuge (a 30 minute trip).
So, it is possible to have faster routing on the airport buses.