If he make a side trip to yuzawa? That time should be got snow at there izit? Since yuzawa easy to go from tokyo...

Snowboard is easier for me. I tried both on same day. Within minutes on snowboard i am cruising nicely.. Rusutsu charge some fees to change from ski to snowboard. Some tips for those who doing ski. If you are the not so good at balancing than ski would be easier as you can stand and got stick to support you. If you are good at balancing and played ice skating before, do try out snowboard. Snowboard disadvantages is no standing, so u need to brace urself to keep falling when stop. No problem to fall on snow in Hokkaido as the snow is just too damn powdery!!

In Japan, they have already planned the route nicely for you, so if you ask is it doable, yes it is doable, however, you will have to walk extremely fast/run to the platform, considering few factors
1. you are not familiar with the train station itself, i.e you dont know which platform/where the train stop
2. Malaysian walking speed is like turtle compared to Japanese.

My advice is not to take the risk and go for better one. From my exp, I always missed train during my last trip to Japan, due to wrong platform / walking too slow (although mention 3 min gap, but i took around 5 min to reach there, etc etc)

None, or very little night life. Far from train station, in/out to nearby city is by bus, forgot already if hourly or twice hourly. Not so much food variety, konbini is small. Other than that, okay la. Lots of onsen/sento, some need schedule to go, others just open, no need to pay.