You aren't going to find a used one that does everything as well as you want for $30K IMO unless it's an older X10. X30 will not make you happy on a ski (New model may but definitely not the old) and PS205 likely won't be big enough. Then again I don't know if I am reading into your expectations of ski wake properly.
40th Anniversaary X14
'97 Prostar 190 - LT-1 (For Sale)
Prior boats - 2009 X14, 2008 X14, 2005 197, 1988 Tristar 190, 1989 Prostar.