You guys sound fun! We've got probably some of the best of all the things you mention right here in the state. highland mountain bike park is the best. I go to Loon for downhill, it's cheaper and less busy (they have a 8 pack lift now). For xc biking there's trails everywhere! Join the NEMBA, a great group of mountain bikers meeting up mostly on week nights.

Skiing has been tough in recent years, climate change is hitting new England hard but we still get a couple good rippable months each year, I do the ikon pass as there are lots of big mountains nearby. If you like back country hit tuckermans ravine.

I'd recommend trips to Canada, it's so close to here and it's amazing for all these activities too!

New Hampshirites are kind of quiet and self contained, it's been a struggle meeting other outgoing people since I moved here. Naturally everything else you listed is found in the white mountains, you'll never get enough, if you want a challenge try "the 48" but be careful and prepared.