Overall I would say "No". If you play hard to get it shows a great level of arrogance & is a real turnoff for guys. It appears that you are superior to others & that the person showing interest in you is not up to your standards & you deserve better.
You can end up with the situation that nobody is interested in you because of your ego & you end up a lonely person.
It can backfire, along with the possibility of the person moving on.
You don't need to be a stalker however it's never a bad idea to show a little interest.
Maybe a little, but if you play too hard you're not going to get "got".
I would say that honesty is the best policy if you are going to get in a long-term relationship with someone you like make your intention both clear this stops you from wasting time arguing with the other person in the long run and prevent both of you from getting hurt.
If you're honest from the start people are more likely to respect you. Personally I don't apologise for know what I want and going after it. If the person doesn't agree with what your looking for with in the relationship it great because you've made you intention clear from the start and don't need to explain much and can just move on and find someone else who fits what you looking for e.g open relationship, friend with benefits, deep monogamous relationship.