Affinity Designer is an excellent option. It’s way beyond what you would expect a $50 app to offer, and bests Adobe Illustrator in several areas.
That said, I think its low price point has started working against it. New releases come at a glacial pace, and a few broken features have literally had fixes in the works for years (expand stroke is the standout). When the last thing I bought from the company was a $50 purchase four years ago, I can’t really complain, but in retrospect, I wish Affinity had gone the Sketch route with an annual upgrade program. I’d like to pay more to see Affinity Designer advance faster, but presently there’s no option to do so.
Seconded. It's just different enough from Illustrator to be unsettling for the first few days, but the core of it is immediately and very obviously excellent. I persevered (it's vastly less money) and I'm very pleased I did. It's significantly smoother and faster in daily use than Illustrator (at least on my machine) and that counts for a lot for me. Updates are thoughtful and contain useful features. There's very little now that I actually have to work around and some parts of it are just intrinsically better - snapping candidates, for example.
I'm really liking it myself. Unfortunately I've got hundreds of hours wrapped up in making maps that I periodically update, and there's no good path to move them from Illustrator to Designer. PDFs move, but then every path comes over weird... And without the layers and groupings that are otherwise so helpful.
