Have you thought about what options you have for aeration? It provides lots of other benefits and is good insurance for the brutal winter years.

otherwise, I would say try to understand what made the water quality different this year since you said the snow fall was less and the amount of ice is 'typical'. Drill a hole and sample water now and see what you can tell about it?

or.. hope like crazy that global warming is real and continues to worsen rapidly so that winter time is months shorter than it is now...