I think by the end of the last winter season, Finnish and Swedish Lapland had proved most consistent. I've previously been told by Finns living in Lapland that February/March is a better bet because the weather is colder, so less choppy weather/cloud. I don't know if you could get a short break with one of the ski travel specialists like Inghams. They do several Finnish Lapp resorts. Discover the World do short breaks to Swedish Lapland to visit the Ice Hotel and/or see the lights at Abisko direct flights to Kiruna, I think, but they are ??????. One of our less frequent posters last year said that she'd read the lights were more reliable around the solstices - I'd check on that before booking anything though.