You have to judge a programme on what it is, not what you want or think it is.
Affinity Designer is not actually designed to be a vector design program. I am both annoyed and indignant that Serif markets it (also) as a vector design program. They are so aggressive in their marketing that it ends up on the edge of truth. Their labels "styles" and "vector brushes" are pure nonsense. "Styles" are apply once presets and "vector brushes" bitmap brushes on a vector path. etc.
Designer is essentially a program that controls bitmaps via vector elements, and that even when you try to make vector-only outputs rasterizes way too much. There are no more vector features in Affinity Designer than in many small programs. They're just beautifully implemented.
A shame. As a design program for more artistic complete designs that end up as bitmap, or is bitmap, Designer works excellently, bitmap and raster can be mixed without thinking about the technique, and the programs are lightning fast. If you look at the work done in Affinity, it is obvious that the program's potential is being exploited to the full. Out there.
I haven't experienced real alternatives to Affinity Designer in the program's own true genre measured in ease of use, easy workflows and raw speed, while Illustrator and CorelDRAW may get unexpected competition from Vectorstyler one day.