Hi Alex, welcome to the forum. I'm in the same age bracket as you, a sports flyer and just up the road in Brisbane, hope I can help in some small way.
Firstly what Transmitter do you have ?
I agree with the others, a conversion to FBL would give you a more positive experience.
You need to have some negative pitch to hold the machine on the ground while spooling up, otherwise the smallest gust of wind will tip the heli over on the ground.
To get the Gyro out of HH depends on what transmitter your using for Spektrum some of the early ones, above a Tx Gyro setting of 50% Plus is HH and below is Rate mode, on my DX9 above 0% is HH and Negatine % is Rate mode.
To convert to FBL you would need a Flight controller (FC) and a 600 DCF main shaft to match the (Direct Flight Control) head you have. For an FC I use iKon but Vbar, BeastX, Spirit etc are also excellent it is a matter of personal choice.
The vibration on start up is either a bent Main shaft, too much vertical play in the main shaft, unbalanced blades, missing gear teeth or damage belt if belt drive or something else not up to spec.
I think you you only use the ESC signal wire but not sure as I have never set mine up that way.
You have a Flying club in you area
Home - PARCS - Peninsula Aeronautical Radio Control Society they have all disciplines of RC flying they may also be of use to you.
And finally our local source of helicopters & parts is
Australia's largest FREE radio control classifieds website.
Hope this helps, Stay safe!