Having a good room will certainly help you identify what's wrong with your mix. That's why room tuning is a major part of our flagship program, The Reverse Engineer™.
But just like training your ears, there are stages to this process. You don't need a perfect room to significantly improve your mixes. You should continue to improve the quality of your work while gaining new knowledge IN TANDEM with improving on your room over the long-term. Otherwise, you'll get stuck on your room and won't make any progress until you have the "perfect" setup... which we both know doesn't really exist.