Hey Redhawk- I just got back from 4 more days at Big sky, did 3 days there last year. First, the mountain is huge. The runs are long, even the single chair runs. Depending on what you're looking for I can tell you a few of my favorite places, here's as brief of a rundown as I can provide:
The mountain village- Swift Current Chair is mainly for getting other places (in my style of skiing). The runs down that side are long but boring, depending on what you're looking for. Lots of blue groomers. Jerry lives here. Ramcharger is a heated bubbled 8-seater which is super cool. Most of the runs there are also groomers and get skied off quickly. What is of great value here is Everett's 8800 for lunch. Make a reservation now. Your wife will thank you.
Powder Seeker is a heated 6 seat bubble that serves a cool bowl. If the conditions are right these are fun shortish steep bump runs. This also gets you to the Lone Peak Tram. If you are an expert skier then ski the tram. The easiest way off is the back side, Liberty Bowl. It's worth doing just to say you did it. That is one of the most terrifying lifts I've ever been on but I don't regret it. Liberty bowl is expert territory but is manageable by an advanced intermediate. If you want to do the tram do it in the morning only. By the afternoon the visibility is usually terrible up there when the wind builds and the line gets long.
Moonlight Basin- 6 shooter chair is very long and gets windy at the top. It's only worth going up if you take the next chair, Lone Tree which opens up an entire side of the mountain. If you want the hard stuff there take Lookout Ridge to some of the tree runs, like Single Jack and Double Jack. They are both super fun. There is a very long blue groomer called Horseshoe that is fun if you just want to cruise. I think I saw one other person on the entire run, which is probably 3 miles long (or more).
Andesite Mountain- (left on the map) is accessed initially by Ramcharger. The stuff under Thunder Wolf is fun and long. The bump run right under the chair is only meant for people who really want to ski bumps. It's super long and hard to bail out of, so buckle up! The blue ridge on looker's right is long and has a double fall line, which I didn't enjoy. The blue on lookers left is long and fun but gets skied out.
Below Andesite mountain is Flatiron Mountain, and the Lone Moose Chair. That chair is a slow 3-pack and serves 5 runs- 2 greens, 3 blacks. I found the best snow on the mountain there 6 days after the last snowfall. It was awesome but you better like steep or green, and you need to be willing to ride a slow chair. No one was there on a Saturday and the snow was soft and deep where everything else was scratched out. You access this from the bottom of Thunder Wolf.
Finally, my favorite part of Big Sky is the back side. Specifically Dakota Chair. No one goes there and the best skiing is to be found there. A lot of glades, one really nice groomer under the lift, and a couple of hike-to areas. The chair is slow but the area is amazing. The other back side chair, Shedhorn is also fun, but not as good as Dakota.
There is much more than that at Big Sky, including some super gnarly stuff that has to be hiked to. If you have any specific questions fire away or PM me. Have fun!