I had an impossible idea before, hahaha.
The player train the mounted Teutonic Knights at the castle instead of the unmounted one.
The mounted Teutonic Knights have the good moving speed and can get the bloodline and barding armors like other cavalry but their basic HP are low (maybe 50), which make them easy to be “unmounted”.
Similar to Konniks, if the mounted Teutonic Knights gets killed, they will be switched to current unmounted Teutonic Knights, who have great damage and HP but only 0.7 (or 0.8 now) speed.