i am seeing more and more rocking the NTN setup, but honestly.. just go hammerheads as far as bindings are concerned. you can find them used everywhere for around $100 to $135. the Vice's are nice but the hammerhead still gives you a better range of stiffness settings so you can fine tune and figure out exactly what you want for the park. for me it is setting 4.. make sure the binding is still soft enough to do tele slides and presses or what is the point? =)
skis you can pretty much go any direction. i currently have the Alpha 2s center mounted, which feels a bit weird at first but is nice after you put some time into it. note, center mounted teles look ridiculous! i also have some Armada Alpha 1s being mounted as well 1 cm behind true center. i have had great luck with these skis in the park. my buddy rides the K2 Domains and treats them as all mountain/park and loves them!
let me know if you have any more questions!