Mac Studio external storage options for photo editing

I need some ideas for my next-gen desktop storage set up: Currently I have a Mac Studio which I use for professional level photo editing (using both Lightroom and Photoshop), I will keep this. Connected to the Mac I have a primary storage 4TB external HHD, a secondary 4 TB HHD back up, and a third one as well. I use the primary HHD for storing my work as I move images in & out of editing. But all three drives will reach full capacity shortly.

So I don't know where to go from here. I like the idea of keeping a triple storage setup. I don't know if I should keep these three drives and add three more (like 4 TB each), or get a couple, maybe 3 more, huge drives (8 - 10 TB each) and transfer all my files over to them. I'd like my primary storage drive to be an SSD so I could gain a bit of transfer speed.

Any thought, ideas, input will be appreciated.