The suggested price of 15M for 32TPE is because it costs 3.2M to re-allocate your TPE. Which makes sense since the new rule allows you to put your TPE wherever you want. However I don't think most users earn high enough or care about Speed so much that they re-allocate every single time.
My suggestion for the new structure is;
2M -> 5 TPE
4M -> 10 TPE
6M -> 15 TPE
8M -> 20 TPE
10M -> 25 TPE
12M -> 30 TPE
My suggestion for the new structure is;
2M -> 5 TPE
4M -> 10 TPE
6M -> 15 TPE
8M -> 20 TPE
10M -> 25 TPE
12M -> 30 TPE