I want the new modern email format 100% of the time

I have had Comcast for over 36 years and my biggest complaint is the inconsistency of the email appearance. One minute I have this new very modern looking email format and with the next email... right back to the old boring format that I left for another. I want the NEW style All the time. Why is this so hard to do?? I want the modern look all of the time, who doesn't?