You were fortunate. Every M11 I pick up has a gritty heavy trigger. Almost every other SIG I try has a very good OTB trigger. Phosphating gets a vote especially if the finishing is not great.
Having better sights, beavertail already in the CNC software, hammer and better FCG QC is attainable without more than a 5% cost I would venture. The sights and beavertail would add 1% max. A redesigned trigger would also be nice. They actually had it right with the PreB on the shape. Again, there are some features like sights and beavertail that are universally better.