PIPE
I can clearly understand your problem. Over the years I've
helped ,(or tried to) several flyers with the same problem
of needing to be behind the model to take off. I can only
offer this suggestion , practice your take offs.

Put your plane in the middle of the runway and go for it.
if it doesn't feel rite or isn't working out, power down ,
turn around and do it again until you get it. Eventually
you'll do it or others will tire and then suggest you
stand behind the plane. It's a bit of a ride but if that
doesn't work you are
more than welcome to fly with me as I could care less
where you stand ,(or sit)when your in the air. Just let
me know when your on the runway.

Regards
Roby