having been to both.... i would recommend you go to fernie.
whether you are a park rat, steep and deep, or a complete noob, Big White will get boring far more quickly than Fernie over an entire season.
Fernie is a real one horse, one street, South Park kinda town. and being an ex-mining town, what would you expect. the on hill resort is tiny, but okay.... even tho the bar closed stoopid early and the last bus to fernie town (where we stayed) left stoopid early too.
Big White bigs up its 'family' image. its pistes and lifts are groomed more than the 'wilds' of fernie but are far less challenging.
as far as being snow sure, both get dumped.... but Big White gets its name from the white outs it suffers rather than any mass of snow; and Fernie can suffer too much snow, where slab slides have been known to start at the top and have debris fields near the bottom; ie the whole places closes down.
and needless to say, being in the interior both can get brutally chilly.
but with all that said, you'll have a tip top tiome at either; but personally Fernie FTW.
Just coz you don't understand it
Doesn't mean it makes no sense!