You're right about not removing useless quotes. I mostly do it when on cellphone as it become a pain not to mess up what I actually wanted to quote. Guess I should take the habit to clean the unwanted stuff.
Quoting some posts is not a problem and in fact it is necessary sometimes, but doing it too often, or adding too many lengthy quotes into your posts will bore most of the users. You should also remember that there are many threads where most of posts haven't received good merits or any merits at all.
As JayJuanGee said, that you should give some time to research and learning here so you can contribute some good stuff to the forum that will probably be admired by the active and contributing users of forum. You should also read the posts that have been merited most of the time so you can see which posts can get you merits for your contributions.
You can check LoyceV thread
https://bitcointalk.org/index.php?topic=5053587.0 where he listed most merited topics as it can give you some insight to posts topics that have been admired, and have gained the posters as well as other contributors some merit points.