Is there any reason this routine wouldn't work?

[Yedda]

Right now I am using a soapnut wash, followed up with a catnip tea rinse (let soak for one hour and rinse out.) This is working pretty good for me.

I am thinking about adding a molasses pre-treatment (half hour soak) before the soapnut wash and catnip tea rinse.

I also am using/plan to use cassia once a month.

Is there any reason these things wouldn't work well together?

[mira-chan]

Everything should work fine with the things you are planning to use. As far as I know there are no known major incompatibilities there.

That said there is always the element of water reacting badly with something or some combination spontaneously producing massive buildup. You never know until you try.