What feels acceptable to one person isn't so nice for another person.
I totally understand the desire to make the stock striker fired pistols have better triggers and better groups. It's tough to shoot a CZ with a nice trigger that shoots good groups and then shoot something that drags, bumps, stops, jumps, slides before releasing the striker and then shoots 4" groups at 15 yds.
Now, 4" might be totally acceptable to some people "for a defensive pistol". That's a phrase I see/read sometimes that people use to justify the performance of what they bought/carry. Not acceptable for me, not if I can get something (or modify something) to shoot better.
Why carry an M&P 9MM that shoots like this:
When you can carry something that shoots like this:
The M&P is doing better these days. After buying/installing an Apex trigger kit and an Apex match barrel. Still not up to the P07 standards but quite a bit better.
A nice trigger is...nice. Some people can shoot an ugly triggered gun just fine, but it doesn't make the gun more accurate, more reliable or more fun to shoot.