+1 to adding strength training/functional fitness. This helped me drop 5-6 pounds last winter. Right now, I've reached a plateau and I'm trying to switch a lot of things up with both eating and exercise. Reducing grains does work, especially at first.
There's no way I could spin or do the trainer for 90 minutes. Generally 45 minutes on the trainer and an hour spin is all I can take. If you have any snow around, what about sow shoeing, up some hills?
It's a fine line between fueling your efforts and not eating so much you can't lose. Although it's counter intuitive, sometimes, backing off of hard efforts while losing weight, helps. I've found my days of greatest loss comes during my rest days or days when I just walk or do an easy spin on the trainer.
2015 Trek Silque SSL
Specialized Oura
2011 Guru Praemio
Specialized Oura
2017 Specialized Ariel Sport