40% rice bran is too much for my taste, in this recipe it shows 16% linoleic+linolenic content and despite people usually going for something around that number, I've had dossy batches even when I've limited it at 15 and going for something a little below. YMMV though, just keep that in mind for reference. Olive oil IMHO would fit the bill better at that %, if it's too expensive you can go for pomace or high oleic sunflower oil - JM2C.
Other than that - yeah, the castor may be a little too much, it and the butters are more on the expensive side where I live, so there's that to consider if you are worried about the expenses of the soap you make.
You can try the recipe the way it is, it may suit your needs and preferences. Will it make soap? Sure. Would you like it? Not necessarily, but you won't know unless you try and see what you want to change.
Oh, and I haven't noticed smell from soap with lard - but I've used it only once so far and the bars were scented, so maybe my experience isn't proof of that. I've heard that depends on where you got the lard from and how it was rendered, but overall it's cheap and good for soap, so you can try adding some in your recipe in case you don't want palm oil in it. Both make nice soap at 30-50%, but you can adjust that number lower or higher, according to your taste