I used to use Anarchy (or.. I think they had to change name?) but Arch itself has an installer new (as of last month or so), so I'll just use that next time.
I am testing it. Died on me when applying the desktop config, but I haven't been able to toy with it for long.
It is very, very promising. It spits a JSON that can be used for reproducible installs. It is also very flexible in which you can use the API with custom python install scripts. Very impressive and ergonomic.