I've ridden at Suginohara off and on for the last 13yrs, and it is one of my favourite mid-winter resorts. I've written mid-winter powder reviews of the place from a snowboarders perspective, but seeing as (as my buddy puts it,) I've gone to the dark-side during the spring, aka skiing, I'll write about my experiences with that.
First off, Suginohara is big! There are pistes everywhere so you have a huge choice of slopes from super mellow greens, to crazy steep mogul lines. For me being relatively n00b to skiing, I mostly stuck to top to bottom runs down the length of the Gondola -The Giant Course plus the Shirakaba Course. That's not even to the top of the mountain and it's still at least 3km of wide open piste. Great fun for just bombing and cruising around... But damn, that's some serious leg burn towards the bottom!
The thing about Suginohara is it's S.E. facing so it gets a ton of sunshine. The day before's slush turns to ice overnight, and needs to warm up a touch in the morning else it's a bit like like trying to ski on an ice-rink. So, if I were planning a spring-time trip, I'd look to get there around 9:30am~10ish -no need for first lifts unless your edges are sharp! That being said, when I went, during the weekend, the place was EMPTY! A week or 2 before the resort closed, plenty of soft spring corn, and I maybe encountered 3 people going top to bottom! I had the piste to myself -it was awesome!
Suginohara has super easy access straight off the highway. The restaurants serve decent food. The lifts are speedy with minimal queues -especially during the spring!
The also have a big park with a variety of jumps -nothing competition size or anything, but they do have a ton of rails and boxes. They have rails & boxes in almost every configuration & size you can imagine -there must be a good 10~15 at least.
If only Suginohara stayed open longer... I think it's one of the first resorts to close for the season which is a massive shame as there's still so much snow there...