The MAF has a direct effect on transmission line pressure. A dirty MAF can cause low line pressure.
Something else on this note- Changing/Upgrading your MAF sensor to a larger one, porting your throttle body, larger intake piping ALL effect MAF signal. When you make the pathway larger you slow down airflow across the MAF sensor and guess what- lower trans line pressure, especially at WOT on the high end of the scale. Not something you think about but when you experience it first hand and see the results you never forget.
We started to offer a Combo Kit for the Transgo Shift Kit as it includes a new filter and required gaskets to install the shift kit. The basic $64.95 kit is considered a rebuilders kit and does not include any gaskets. As a bare minimum the accumulator body gasket should be replaced if you are going to install any shift kit.
As Bill said above the shift kit will help to clean up your shifts but is not going to address your whole problem. The whine noise could be a number of things. You mention it happening in gear, but does it make the noise if sitting stopped while in gear? There are a lot of posibilities and some are fairly common in these transmissions that will cause a whine. Also check your engine accessories and idler pullies- they can fool you and make plenty of noise and a stethoscope will help isolate the source. Your slippage on take-off and banging into gear could be result of a few other problems and most likely worn seals and worn input clutch apply piston as this is fairly common. Here is more info on this-
No Forward Cold