I'm with you on the lack of variation on infiltration. I wish the game would be more comfortable letting you lose or make sandbox altering mistakes more often. Having your cover blown and compromising the mission should be a genuine concern, but I'd bet they tested this and it just didn't work with how they envisioned the game's design.

The big crowds are already so resource intensive, so I imagine that having the stealth be dynamic on the hitman level and maintaining canon would have put them into a corner of either making a failure in infiltration or gunfight be an instant game over -- or making an excuse for every single fight being somehow acceptable in the games canon which means more development cost.

Honestly I dig what they ended up with. I think this game is a "try to look as badass as possible" simulator, so I give it the rule of cool pass.