I am having a similar problem. I also keep thousands of notes and a huge part of my organization is the internal links system -- I have the link color coded so I know at a glance to where they go or what they pertain to, since often times titles alone aren't good enough. Now the colors I use for that are completely removed and I can't update new ones to match and I do not have the time to go through 3,000 some odd notes to track down and change my whole system. I tried to keep things simple in the past and only used the color pencil themed color selector to try to keep things consistent. It was what 20 colors? At most? surely that isn't too much to ask for. This issue is so serve for me that I cannot work in EN like this. I will either have to find a way to downgrade to a previous version or (I shudder at the thought) move platforms. I hate OneNote but if I can't use colored text outside these specific 8 colors I can't stay on EN - it's a deal breaker.