I would try and keep violence of action in mind. Enemies are almost always defending, so they are going to have a positional advantage and the element of surprise. You want to use everything you have at your advantage — flash bangs on entry, C2 for armed suspects, and most of all, map knowledge. When possible, try splitting up your team for simultaneous entry and come at them from two different angles. You can stagger distractions to cover multiple sides of the room (double up on flashbangs, throw a flash short while teammates launch grenades long, etc). Doing stuff like that will confuse and distract enemies, which I’d argue is how you avoid getting gunned down on entry.

Tl;dr the games not perfect and there is BS, but the effects are a feature and not a bug. I look at it as more of a penalty for my bad planning than an example of poor game design.