Sacred Haven of Debauchery

What do backstabs and agility have to do with it?

You're the one mixing things up. Backstabs or attacks from behind cover are still attacks when you're not prepared for them.

It was implied that in Half-Life, it's just shooting, you shoot and hide, and it's fast. Or it's you or them.

In Half-Life? Are you confusing it with Counter-Strike? In Half-Life, there's actually a lively firefight, people jump around, run back and forth. Of course, there are campers, but you can't do without them, and in Might and Magic, there are people who only use bows. And if you sit in one place, then sorry, you've killed all the dynamics yourself. It's still harder to land a headshot on a moving target than on a stationary one. However, you answered everything yourself:

Might and Magic is what I like the most.

Whether something is liked or disliked is purely individual. You didn't find what you wanted in Half-Life/Unreal Tournament, but you found it in Might and Magic. But those who have enjoyed Unreal Tournament, Half-Life, Rune, Quake won't find enough dynamics in Might and Magic. Yes, the game may be enjoyable and good, but it's different, and there's less dynamics in it precisely because it's made differently. It doesn't need more. It's not a minus or a plus, it's just less, and that's all.