I think you can use any board you like. If you want a rounded rail on your kiteboard then get out the sander and round it off, then afterwards apply a thin layer of epoxy. However why? Why not use a wakeboard a the park? the simple reason is cost. You can get a used wakeboard for $25, or even a brand new pro model for $250. contrast that to a pro level kiteboard like the hadlow for $1,000 or the wakestyle north board like the gambler for $800. Even if you have a kiteboard that has that wake style bottom, it's still vastly more expensive than a wakeboard and it really sucks when you snap a kiteboard at the park. That said I do ride my kiteboard at the park, why because I want to no other reason. I would not buy a kiteboard specifically to ride in the park. I would only buy a kiteboard to kite with and then if you feel like it take it to the park a couple of times. it's so much cheaper to buy a wakeboard than a kiteboard. doesn't make any sense to ride a kiteboard at the park if you go there a lot. You don't want to be so worried about hurting your board that you stay off the terrain.
Also the Nobile 50fifty is suitable to kite and park?
About raised edge, in wakeboarding the boards have curved edge like you say, they help with sliders and such so you don't catch an edge
Can you give an example of a board with a curved edge? I would be really interested in trying one, as I've caught more back edges than is healthy for me. Every time I land blind without digging an edge I thank my personal deity.
I don't think they are meant to make it easier to not catch an edge when landing blind, it's more for hitting feature in wakepark and not catch an edge on sliders.
It's just how round/sharp is the edge on the board. In wakeboarding it's pretty common to look at those in the specs, for kite board cross over doesn't look like that info is available...
By the way Saul Custom has a few boards with a grind base too.