Daily urban commuter here. I've had coaster brakes in the past. Bendix, Shimano, and Sturmey-Archer. I was attracted to the simplicity and lack of exposed cables. All were well maintained, by me, on wheels that I built.

Concurring with what you say, I learned all of the obscure failure modes of coaster brakes the hard way. Today I would not put them on anything but a maybe a kids' bike or beach cruiser. You can't guarantee that your feet will be in the right place at the right time to stop the bike.

Among other failures, I've experienced coaster brake "fading" on a descent when my house was at the top of a hill.

Adding a front brake is an improvement but not a panacea. You really need reliable two-wheel braking. It's not just for redundancy but for actual control of the bike during hard braking.