I don't have your year carb but if you are adjusting the pilot mixture screw and it isnt doing much. I would check to see that all the parts are there for pilot needle screw, spring and o ring. A bad oring on the screw can cause problems. You might replace the pilot screw assembly. I would replace the pilot jet with a new one in the stock size, maybe buy a larger one for later to try. I would also try and clean the pilot jet area again. Remove the pilot screw and also the pilot jet to do this. Your carb and all the parts have to be good, also clean before trying to tune the carb. May sure you don't have carb boot air leaks. This can cause a lot of idling problems.Spray WD-40 by the boots when the bike is running if it speeds up you have boot air leaks. Under the tech stickies Lizrdbrth has the procedure for adjusting and tuning a carb. Carefully read that. After you get it idling right then you can try shims on the needle to improve acceration. My bike had a hesitation the shims fixed caused by a pipe.
I haven't messed with my clutch except to remove it to install a kick starter. It's not hard but you need to learn what to do. Plus there is a cover gasket that is a pain to R and R. That being said our clutches seem to let out near the top. Check your spring where the lever comes out of the motor on the left side to see if it is on where it should be.
Have fun learning this stuff it is rewarding.