Ellis, that thickness is about perfect and is infact slightly thicker than what ice rinks in N America have, but they are maintained exceptionally well and are used for hockey and figure skating only. Public skating doesn't really exist. Even still, you'd have to really hack away with a heel to go deeper than 35mm, it's thicker than you think in terms of ice.
The thicker the ice the worse the quality and the softer it gets. Also it is probably worth noting that the new rink will be on a concrete rather than sand base which allows a better quality and shallower ice, unlike the BBT or WNIR.
As for sharpening; it's down to preference. Most players go with a 3/8" radius and then 1/2" follows close behind. If the ice is good and hard you can generally get away with having a deeper hollow. Soft ice with a deep hollow will slow you down a bit so in most rinks in the UK I personally would go with a shallower grind.
If you get an option at the moment though I would be amazed. Sharpening over here is awful, if you explain to the majority of staff in the BBT that you want a 1/2" grind they look at you as if you've spoken a foreign language. I hope that in the new rink they take time to train good staff on the ways to operate a rink and keep the ice in good condition, I include skate sharpening in that too. I don't doubt this will happen though, Greenbank from what I've seen so far seen a real quality outfit. But playing over in Canada even in local rinks really makes you realise how some really passionate people can get even the most run down rinks like a sheet of glass.