bulgaria is up and coming, in that it has cheap labour and has entered the european holiday market; its primary resorts are Borovets and Bansko and they are in no way 'snow sure'. and when it does snow (if it snows) it might not last very long. but it is cheap.
switzerland meanwhile is high altitude and has demanding terrain. zermatt has a glacier; has an excellent lift system; is a car free village (you use electirc golf carts to get about; toy town stylee) and is fucking expensive!
for demanding terrain (and i have been to places like whistler, big white and fernie) europe pisses on north america. it really does. you will not be bored especially if you can happily hike.
france has the mass of resorts, many of them dwarfing the twin hills of whist and black comb. look at les arcs - flaine or as mentioned les trois vallees; but also there is espace killy with val d'isere and tignes being on a single lift ticket.
austria consistently has the most snow fall and thus powder days but suffers zee germans and dutch ALOT.
italia has the best wine and the shittiest ski school snakes.
but if it snows, anywhere can rock! most places have terrain parks these days, but personally i think rails are for skateboarders and if there is no park, then take a shovel (which you should for avy extraction ayways) and build your own booter!
scandinavian resorts in finland, norway and sweden have tiny hills but therefore huge fun parks! watch out for icy landings tho!
in the meantime, for your further reading:
Skiinfo - Frontpage - Snow report - Snowfall - Weather - Ski area - Ski holiday vacation