Wire edge, perhaps with lower grits and not alternating sides. But not at sub-micron grits.

Convexing a bevel is a good thing, not a problem. Honing edge leading, on film, over a sheet of paper on a glass substrate, will convex an edge.

The problem most folks have with paste, is making too big a jump and expecting too much from paste, without a progression. An 8-12k jump to 30k is a large jump, especially after a 4k jump from 4-8k progression.

A handful of pasted laps and expecting a magic edge is just not realistic.

That, and it is not just about grit size.