Just another 'I've just finished the series' post

So yeah, just finished anime. Absolutely loved it. Definitely lived up to its fame as one of best anime series.
I was a little bit disappointed with the ending.
Also, I wasn't very happy that since Light gave up ownership of notebook while in confinement, Ryuk's screentime till the end was greatly reduced.
Anyway, I've got some questions:

1. This is one of the animes that follow its manga source closely, right? Was there a lot of left out?
2. Relight movies - as I understand they are recaps of the series, so basically some parts of the episodes put together. Do they add anything important and worth watching?
3. A question for people speaking Japanese - does Misa actually talk in the third person? The subtitles I watched with indicate so.
4. So there is a film series and a tv drama. Are they any good?