The kitchen knives likely are softer and way easier to sharpen. S90v is getting into the upper end of wear resistance. Work on the S30V next. Once that is where you want it, then go to the S90v.
Try marking the edge with a Sharpie between each pass to have a visual indicator of whether the actual edge is making contact with the stone. Black marks on the edge will show where adjustment in holding the angle is needed.
When I sharpen straight razors, I use a cheap digital magnifier ($30ish is good enough) to check the whole length of the edge for uniformity before moving to the next step in the progression. A cheap jeweler’s loupe works too and is better than nothing.
I am in the minority view on here, but on the harder to sharpen steels, I use pretty firm pressure and relatively fewer passes on diamond plates. My thought is a coarse diamond plate cuts quickly. I can keep the angle closer to uniform for five passes to cut a good edge than I can for fifty light passes. Once a crisp edge is cut, then use a light touch to finish it.
The coarse stone is doing most of the work of sharpening. An Atoma 140 can produce an arm hair shaving edge. Everything else is just refining that already made edge.
Do not move off of the coarse stone until there is a really good edge. Only then move to the next step in the progression. Again, the coarse stone is doing the sharpening i.e. making two different flat surfaces intersect in a crisp edge. Everything else is just refining that edge.
Practice on the easier blades. Once those can be done with confidence, then move to the next most challenging blade and
keep practicing. 