Whirly,
The requirement for you to use the same procedures as fw sounds a bit strange - maybe it's a noise abatement thing.
At Barton we have two helicopter training schools - their traffic fits in nicely - they lift , air taxi and cross the active runway and then route out, usually to the North at low level (i.e. below 500ft). This works really well and means that we don't need to worry about rotor vortex as much. About one or two minutes from lift to being out of the ATZ.
Perhaps you should raise the issue with ATC and see if they can accomodate you in a different way.
I had a helicopter trial lesson for a present a couple of years ago, it was half an hour but managed to fit in standard flight and hovering no problem (welll the timing wasn't - the actual hovering was for me
!)