OP, I've recently gone thru updating my freehand stone setup. So, let's say you want a moderate lineup of stones that can sharpen ALL your knife steels from carbon steel to stainless to super steels, without going too crazy cost-wise to start and buying really high end stuff. If I were starting from scratch today, here's what I'd start with that would cover all basic sharpening tasks, and steel types. This is what I wish somebody had told me when I started getting into freehanding a few year ago. Total cost of everything combined, about $250.
*
DMT 3-grit combo of 8" diasharp plates (XC, C, EF -- can skip the F stone, don't need it). Getting them this way saves you some $$, and this set will sharpen every steel you have. $165.
* Can use these for profiling, repairing, and resetting a good toothy edge on any steel using the XC and C plates. And use the EF to apex and finish.
* Note: Some folks here on the site would advise to skip the DMT XC and C stones in this combo, and instead, get a coarse SiC stone, for example, a Norton Crystolon in 240 or 320 grit. You could do that too, and would be much cheaper. But the coarse DMT work pretty well, and you don't have to flatten them. If you get a SiC stone, you have to worry about flattening it regularly.
* Add the
DMT bench stone holder with magnetic adapter for holding any diamond sharpeners including DMT, that are based on steel plates. $24.99
* Add the
Baryonyx Arctic Fox bench stone. $40. I use this stone to sharpen all NON super-steel knives: carbon steel, regular stainless, etc. If you need to profile/repair an edge on these steels
before you sharpen on the AF, your DMT XC works for that. And if you want to refine your edge
after apexing on the AF, go to your DMT EF plate.
* You can, but don't necessarily need to, buy a separate stone holder for the AF stone. I often set mine on top of my DMT holder between the clips, and the rubber feet on top of the DMT hold this stone in place just fine.
* Add a strop of some type. I use a 2x2x12 block of hard basswood together with CBN 1 micron compound. $16 for the compound on the Big River site, the basswood you can get from a hobby store or places online. This is a good option to maintain all your knives.
So all this gives you 4 total stones, a holder, and a strop that will sharpen and maintain every type of steel you have. When you want to get fancy later and start adding more stones that can do more things, you can get lower grit SiC stones for whole blade profiling (I recently got a Norton Crystolon 120 grit stone for this, these are only $23 and work awesome). Or at the other extreme, you can get super high-grit stones like 6k to 8K grit for polishing and refining edges. Like the DMT EEF, or the Baryonyx Ptarmigan. These are more expensive, special purpose stones, but are also awesome. But all these things are extras, definitely not necessary to get great edges and do good general purpose sharpening.
Last thing: If it were me, I'd stay away from ceramics for general purpose sharpening. I've used them, and it's admittedly a subject of some divergence of views on this site: use them for general purpose sharpening, don't use them at all, or use them only for special niche cases, like edge refinement after sharpening. I'm in the last group. Just my 0.02, don't think ceramic benefits you at all for general purpose sharpening, there are much better performing options that are less prone to have issues with the stone itself.
