There are several topics about lye concentrations here because i think that is something confuses us a lot of people at the begining, i was one of them.
I read that you plan to mix your lye outside, while that is fine and a bunch of people do it, my preference is to just mix it on the sink, since, if there are spills or whatever you only need to run water and thats it, while if you mix it somewhere else you are gonna need to take a few more steps. Also you dont need to wear a biohazard suit to work with lye haha, just be careful but a splash wont be too too bad, and the fumes wont make you drop dead. I feel that i read too many alarmist post about the lye (including someone who mixed the lye and went out running), that i really felt it was super dangerous when it really is not that bad.
I also made the mistake of putting too much castor on my first recipe, but i asked for feedback like you and people told me it was too much. Thats what prompted me to search for “apropiate” amounts of different oils. Same for the lye %
Finally i would also leave the colorants for a future batch, you dont need to make things harder on yourself.