Just for fun, I did some calculations with, for example, Bank 1 15 years + KFW 10:
After 10 years Kfw, you still have 68,225 left. To pay that off in the remaining 20 years, you would have to put 528€ on the table starting from year 10.
To pay 136,715€ with 5% interest in the remaining 20 years, you have to put 902€ on the table. (The interest for this period amounts to 79k). According to your sheet, however, it is only 61,695...)
Regardless, after 10 years you have a jump from 1,060 to ~1,300, and from year 15 to 1,430€. But that is completely lost in your overview.