Hi again, cthiggin!
Yes, you've pretty much got it. 😀 What's normally the throttle for a fixed wing on your stick does the job of the collective lever in the helicopter. It has very little to do with the engine power output and almost nothing to do with forward thrust.
In most helos on the sim, the engine power is controlled by the computer, so all you have to think about is the amount of lift you are requiring from the rotors and there are no worries about the throttle.
You're quite right- in real helos, the pilot has control over the engine power output too. A lot of helos have a twist grip on the collective lever, but multi-engine helicopters tend to heve the throttles mounted on the overhead panel.
As you have probably gathered by now, if you're able to hover and land (and well done on that), a helicopter's forward speed is determined by the movement of the cyclic- the joystick. I know it takes some getting used to! Think of it as a role reversal from fixed wing- the stick determines forward movement, whilst the collective determines lift. (There's more to it than that, but we can always go into that later.)
With helos it's a case of seat of the pants flying- learning to balance all the control inputs. Once you get there, it's really worth it, because you'll have control of one of the most difficult flying machines ever put on this earth, and that's really something!!
As always, hope I've helped!
Please let me know how you get on. Best of luck. Talk soon.
Lee