If you are doing your own knives, I recommend the 150 for most chip repairs. If you are doing major chip repairs and lots of them, the 60 grit and 24 grit (Aratae) are the way to go. Better than a diamond plate in most instances.
The 24 grit will flatten the 60 grit. You CAN flatten the 60 and 24 with the Atoma, but I wouldn't recommend it. The problem is that the diamond will flatten through the individual particles in the coarse stone, and the stone will be less aggressive, essentially texturizing the coarse stone. So you need to rough it up with a piece of the coarse stone or a whole coarse stone.
The 24 and 60 grit work best at high pressure. At light pressure they don't get traction.
So to flatten a 24 grit stone the best choice is another 24 grit stone, ideally two of them, with stone a vs b, then b vs c and a vs c.
Being less of a purist, just use 2 stones. To date I have not needed to flatten my 24 grit stone