I have Sketch and Affinity designer, and both are very good programs, but for raw SVG-ing (where I want full compatibility or anything similar) I still use Inkscape. It works, and works well, I'm not sure what your issues may be but I've been using it for, like, 8 years already (on Mac, I mean) and the latest versions are the best so far. Same for Gimp. I usually use Pixelmator, but Gimp is my second option (and depending on what I want to do, first option.)
Keep in mind there are "native" apps now for both Gimp and Inkscape (i.e. no longer requiring X11 open and using C- bindings, I'm not sure if for Inkscape it's a fork or what, though, been a long time since I installed it). This has made working with them much better for me.