if you want some kind of kit i would suggest a diamond stone as the low grit one. Atoma 400 or DMT coarse.
And if you want a coarse stone the shapton glass 500 double thick is good and fast. The best thing about it is that its almost as fast as the 220ies but wears much much slower. However a good 220 is actually faster than diamonds i have noticed.
then above that you can basically go 2 different routes, you either stop at a 3-4k or so. or lower like 2k.
you could use a 500 and a 2k. 500 and 3k, or a 1k and a 2k. or 1k and 3/4k.
At work i have a dmt coarse, shapton pro 1k and a pro 2k. thats all i really need to sharpen any knife fast and efficient.
I gave my cousin a glass 500 and a glass 3k. those can handle anything. and its fast and dish resistant.
Usually I'd say the 1k stone is the base stone. so you would need a 1k and then something finer and then something coarser.
but if you have a 500 then you wont need a 1k.
glass 500/3k very good combo, the 500 and shapton pro/glass 2k also good.
I could probably get by with only a coarse diamond stone and a 2-3k if I really wanted.
But why have only 2 stones when you can have 15??
wheres the fun in that?