I'd probably hold off on spending the money on PP if you are going to sell it. I don't think it will net you much more in the sale. I'm not sure what you mean by joystick tower. Is that and extended pylon?? If so I say buy it and if you move to an X9 take it with you or sell it separate from the maristar. The rest of the improvements (compound and buff, swim pad, dash) will net you more on resale IMO.
'97 Prostar 190 - LT-1
Prior boats - 2009 X14, 2008 X14, 2005 197, 1988 Tristar 190, 1989 Prostar.