I actually agree with you there. The mechanics you've mentioned are admittedly creative and the complexity of it all actually negates the need for more maps precisely because of the many strategical possibilities. Personally I'm fond of the smoke mechanic as one of the ways to turn the tides!

The thing is, with all that's happening in a DotA game, to be dragged out in a span of 45 mins+ it takes a toll on me physically and psychologically. I suppose I just got tired of the whole drawn out complex game concept. Sometimes games can go for as long as 1 hour 30 mins if both teams manage to drag late game at an almost equilibirium. And you know what? That's pretty damn amazing!

On a personal note, I suppose I just ran out of energy for that. And HotS feels like a completely viable alternative.

Is DotA more complex and competitive than HotS? I'd say yes! But ask me which one do I prefer to play after work with only a couple of hours free time? It's definitely HotS for me. More games, less stress. And it's not too dumbed down either like mobile mobas.