The 1.5k and 2k photos show burrs, not rolled edges. This is not a matter of semantics. A rolled edge comes from lifting the spine. A burr comes from excessive pressure and/or back honing.

The 5k still has a slight, but much reduced burr.

The 8k and 12/15k are failing to reach the edge. You said that you spend the bulk of your time on the 5k and 8k. That may be part of the problem. You really don't need to spend much time on the 8k. Also, you said that you are doing maybe 25 strokes on the 12/15. I have not used your particular hone set, but if they are anything at all like the Shapton Pros, you are doing WAY too many strokes on the 8k and 12/15k. Try doing only 10-15 strokes on the 8k and no more than 10 on the 12/15k.

Also, are you using tape? If so, you definitely need fresh tape on each of those last two hones? Worn tape lowers the spine and lifts the edge away from the hone.