Keyboard modifier shortcuts and their uses

[GroundXaero]

Photoshop has a pretty elegant and consistent solution for modifier key usage in a majority of their tools: shift to constrain ratio, alt to modify around centre / origin, ctrl to modify specific points, warp selections etc. also with sensible default options for snapping and edge magnetism

 

None of this seems to be a default or perhaps even possible thing in Affinity Photo as far as I can tell?

 

For example, using the crop tool in Photoshop, it magnetises to the edges of the canvas and allows for the aforementioned modifier keys to constrain as described. Such a thing in Affinity seems like a chore and if the potential to do this is there and I just haven't found it, then it should be a default regardless in my opinion.

 

Thoughts?