As a whole, it is always better to have more tactical options than less, so for game play reasons the suggestion that you cite is completely unacceptable.
2. And yes, TIE does exist. Just ask the teams who go out and play the New York Knicks this season. If you apply this type of logic, then CT shouldn't exist either. If teams should choose to be able to pick up the intensity against a specific team (CT), how is it that they never choose to lower it to conserve strength (TIE)? I repeat, this happens all the time in real games. In an 82-game season teams tend to pace themselves when effort is concerned. That is why weak teams sometimes come up with surprising victories.
Not only is it a terrible idea, but it is also going to kill the player base in the long run.
Scrapping TIE will make it exponentially harder for teams that are somewhat weaker to beat stronger teams.
I am not even going to go into the fact that the importance of planning how you play over the course of your season gets significantly diminished, as you're no longer able to throw certain games in order to concentrate on others.