Sounds like it might be worth while for you to start over from the beginning...if you fiddle with different things long enough, it's possible that one or more are off to the point that it's just not going to work. I have the same heli and engine as you and it runs great, so here's my step by step.
1. My hovering pitch curve is set up so that I'm hovering at about 5.5 degrees of pitch at half throttle and just below 3/4 stick. Confirm that this is what you've got too. (My head speed ends up just below 1800 in the hover, which is high for hovering, but I like it and we can deal with fine tuning your headspeed later.) Set high stick for 9 degrees. Make both your pitch and your throttle curves linear from hovering to max.
2. Reset the low end needle to the factory setting per the manual. Open the main needle 2 turns.
3. New OS #8 glowplug.
4. Fire it up with the throttle trim at full, let it run for a while and slowly advance the stick to get a hover (if it's too rich to get a hover, then lean it 1/4 turn). Note the stick position. If you are not getting a hover at the stick position that produces 5 to 5.5 degrees of pitch, then increase your throttle curve at that stick position until you are getting a hover. If it's lifting off before 5 to 5.5 degrees, then reduce your throttle curve at that point.
5. AFTER hovering for a few minutes, note how much smoke you are getting and set her down.
6. Bring the throttle trim down to 3/4. It should be idling without the clutch engaged. There is simply no reason to try to get it to idle at a lower trim setting than that. You may be trying to tune the carb for a really low idle (say 1/2 or 1/4 trim) and that could be your problem right there. Now rev the throttle a bit from low stick to 1/2 stick. If the response is okay and you have a solid smoke trail (which will vary based on brand of fuel, nitro content, etc.--I'm running CoolPower 30%, so I'm looking for a really solid smoke trail. If you're running Wildcat 15%, then just make sure you're seeing smoke). If the response is lacking, but you've got plenty of smoke in the hover, try leaning the main needle 1/8 turn at a time, and bring it into a hover after each adjustment to make sure you are still getting a nice rich run. If you reach the point where you think further leaning of the main needle is not advisable, but your throttle response is still lacking, then lean the low needle 1/8 turn at a time and retest response (you might want to open the main needle a touch if you find it necessary to lean the low needle--I've never had to touch the low needle).
7. Once you've got decent throttle response and good mixture in the hover, advance the throttle smoothly (but with authority) to max and watch it climb out. Your head speed should stay about the same and the smoke trail should be consistent. If it's going lean on you, open up the main needle just a touch and try again until you have it right. Vice versa. If the rotor bogs, land it and reduce the high point of your pitch curve a bit at a time until you find that your headspeed stays constant. When doing this MAKE SURE TO KEEP THE PITCH CURVE LINEAR ABOVE THE HOVER POSITION. Ideally, you should inhibit the points in between hover and max, but if this doesn't work out, then just adjust the intermediate points to keep it looking linear.
Hope this helps and that I'm not just telling you stuff you already know.
