I loved this, prototype or not. The suika was fun and felt good, and the idea of nursing a horse back to health so it can regain its true colours was really sweet (plus colour / pattern collection books!).
I could see maybe having the suika phase have several possible "win conditions" (go on until you hit a score goal, or complete a few "quests" (like create 10 hay bales and 2 "bandages" for an injured horse), and an optional "true suika" mode? But I very much enjoyed this as is, great work!