Things have been rough for powder this year. That said, storm rolling in tomorrow that could deliver some goods, albeit wet and heavy. This isn't a bad thing as the cover is still relatively thin out there.
As for mountains for skiing outside the park, in no particular order:
Jay - Most average annual snowfall out of any mountain. Lots of great terrain off the tram. Loads of treeskiing and great sidecountry if you have the means to access it and the knowledge of the area.
Sugarloaf - Great terrain with consistent pitch. Tons of treeskiing thanks to the expansion. Downside is at 200" inches average, they see less snowfall per year than many others on the list.
Smugglers Notch - Great steep terrain, over 300" of snow on average per winter. Great Access to sidecountry. Double lift infrastructure keeps the pow fresher longer, although it slows your laps.
Stowe - Same terrain, snow and sidecountry access as Smuggs but with an updated lift infrastructure.
Mad River Glen - Classic steep, narrow trails with awesome glades. Lift lines can surmount on weekends and busy days though, but again, limited uphill preserves tracks longer. 250" average annual snowfall.
Sugarbush - Similar snowfall as Mad River Glen (they eek out a little more due to higher elevation, but a more modern resort with wider trails and updated lifts. Some great steep options and trees.
Killington - Diversity is the advantage here. Lots of terrain. Not as many drops, but lots of good trees and plenty of trails with pitch. 250" annual average snowfall. Elevation helps bigtime with marginal temperature storms.
Magic Mountain - Southern VT. Tons of steep stuff with drops and solid lines. Tons of work has been done in the glades in recent years. The place is uncrowded, even on weekend powder days which means things stay fresh longer. Annual average snowfall is on the lower side due to being in Southern VT, but when the storms hit, the place goes off.
Whiteface - The slides are amazing when open. The place does not see much snowfall though and there is a reason it has the nickname Iceface. Great terrain though.
Cannon - Great terrain with great steep stuff. Average snowfall is a touch low compared to lots of other places though.
I'm sure I'm missing some awesome places and I'm sure others will toss their favorites into the mix, but the above are the places called out the most for their terrain.
It's the East though, so don't go on any old day and expect to ski powder. You have to be willing to put in the effort of watching storms and dropping everything at moments notice to get after it when things are lining up.