The weight of a shaft mostly affects feel. As for ball speed and swing speed, it all depends on how you load the shaft. Heavier shafts with tend to be stiffer and have a lower ball flight as supposed to a light shaft.

Thanks mate!

I swing around 110mph and need a lower launch and spin rate. Looking at the Motore F1 65. Whiteboard costs too much!!! Haha.

I tend to see a correlation of player size and strength to shaft weight.  Pro football player types tend to need heavier shafts.  Smaller players swing anything.