As an all-around 1-stone solution, the norton 4k/8k is often a suggestion up front. It's easy, big, readily available, and consistent stone to stone. My stone is just like yours. You'll need a DMT to lap it flat (DMT d8c is the standard mate for it), and you'll likely need one anyway. Only problem then is soaking it. FWIW, I'd suggest that instead of a coti...way way easier to get started. All this "learn your stone" is no good if you are simultaneously trying to learn to hone. My 2 pfennigs anyway.
Me to wife (truth!): "Does she really need all these Barbie dolls? You only need two to have a conversation. Why so many?"
Wife, not skipping a beat: "It's kinda like your straight razors..."