Coming from SolidWorks, the single most frustrating thing I'm finding about Fusion is the sketch environment. Most of the features are analogous, but Fusion's colors, line weights, dimension leaders and constraint icons are (to my eye) immensely frustrating.
They look good in a demo. In fact, they look basically fantastic in a screen shot of a well-sorted, clean sketch.
Using them however, is a soup sandwich compared to sketching in SolidWorks (and SW can have some super messy/annoying sketch issues as things get complex at times as well).
1- Color/Contrast
Line colors are ghosted, lightweight and often times difficult to see in every environment setting offered.
2- Line Weights
There is no deliniation of line weights between leaders and sketch lines. There are different line weights for construction geometry, but those lines are often unrecognizeable. I can't even see the construcition geometry in the attached sketch picture. The 10mm dimension leader is absolutely obscuring a sketched line.
3- Constraint Icons are Too Heavy
Constraint icons are very heavy in comparison to all line weights and they seem to dominate whatever geometry they are supposed to be annotating.
I understand that I've got about a decade of SolidWorks experience and transitioning to something as core to a CAD package as a new sketch environment is going to be a pain, but the pure visual experience of Fusion 360 sketching is making it hard to even get a grasp of what's going on. Sure sure, we're all designers here and Fusion is making a name for itself with a super slick interface, but design is also about visual clarity and useability. On those fronts, I think Fusion could use some minor tweeks to find major gains.