No don't get rid of it! Those things are a blast, and will last a long time if you take care of them!
They do use coolant though, it is the same stuff you ride on, that is, the water. The early Kawasakis do blow a bit of smoke. it is nothing more than the 2 stroke mix. It is possible you have a gasket leak, or a leak at the exhaust coupler but you probably don't have any problems at all. If you do develop a leak into the combustion chamber, it will not run properly, and will sieze a piston, probably by now.
Read my other answer about the shutdown procedure and try again.
As to the slipping, you gotta learn to handle that, it is normal. You can add some aftermarket sponsons, but you will lose some performance with the, yet add stability.
