Get something more powder oriented for Japan, especially if you are going to Hokkaido/Japan. Even the more powder focused NS boards like the Cobra are basically groomer/jib sticks in Hokkaido.
I agree with this, if Japan is your main riding location and you come here in the peak season for snow you should think about getting a board that is more powder specific.
Japans powder is some of the best and most consistent in the world. The terrain tends to be gentler especially in Hokkaido.
Although lighter riders tend to float much easier (weight please?) having at least a powder focused all mountain type of deck (like the K2 Ultra dream) is a good move in Japan.
I find the Proto HD to be very good in powder for what it is, a non task specific all mountain deck that will be good at everything without specializing at anything.
I actually prefer to ride it over a powder deck on days when there are smaller powder dumps, that way I can play around in the powder riding switch and doing spins of lips.
If there is a bigger dump I want something more powder focused and capable.
If I only had one deck to ride here in Japan I would go with something that is a more powder focused all mountain deck, something with setback (a little) and longer more gently rising rockered tips. At my weight (78 kilos) I would also move up to a 160 or 161 in this scenario.
If I only had one deck to ride and I rode sometimes in Japan and sometimes in other less powder blessed places (or times of year) I would be very happy with the Proto as my only board.
Ideally two boards will always be better, one for serious powder dumps and one for all round riding (or a park focused deck if thats your thing).
I am very happy with the proto as my do it all deck, but I have a longer powder deck for those special days when the powder is on.
In mid winter here you will want to ride the right deck on a deep day. That could make it a day you will remember for the rest of your life. Sounds dramatic, but its very real.
Unfortunately that might also turn you into a powder junkie and then you will spend hours thinking about powder and boards even though winter is months away
For more suggestions or help please give us more info.
What is your weight?
Where will you ride in Japan?
How long will you be here and when?
How much park?
How much tree runs and free ride?