I've made an RFC for this as well, however I'll simply put some values here. Imo new rocket fuel recipes still leave some room for improvement. I'll cover all 4 eventually, however here is purple first.

Imo, new values for the 3 recipes recently put in the chem plant should be
2000L Hydrogen Peroxide + 2000L Ammonia -> 2000L Hydrazine (30v 320t)
2000L Hydrazine + 2000L Hydrogen + 2 C -> 3000L Monomethylhdrazine (240v 600t)
1000L Monomethylhydrazine + 1000L Nitric acid -> 2000L Purple Fuel (480v 400t)

Can you list the old values and your exact reasoning?