Yes, that's called preload; it effectively raises the spring rate.
You don't want the main coil to have any tension on it before you set the car down. If you've compressed the helper entirely, you're as high as you're going to get, and this will cause bounce as well. The coilover is designed to operate in a butter zone. When you raise it too high, the strut "tops out" when you unload the rear (what happens after your crest a speed bump and the car starts to move downward again).
Removing the helpers is primarily for tire clearance. Cutting bump stops is so you don't bounce off of them when you're super low. I'm fairly certain neither will help you here.
You may have to go lower man, and I'm here to tell you from personal experience: Rokkors are not comfortable, at all. My wife hates them... her chest really hates them... I love them.