1) Yes, definitively faster, althought it is very much due to the lack of options.
2) Around 5-6, wich is about the same as it did in 3.5, especially at level 1
3) Very easy, all you have to do is remember this: (Half character level+ related stat+profiency) and you can Dm almost any game. This is not a good thing according to me.
4) I really don't like it. Everything is so.... BASIC! It plays WAY too much like an mmo, with the cooldowns, the easy raise dead, heck, even the armor types! Fixed exp per monster, you have to get into EXACTLY 10 fights of your level to actually level (way too long if you ask me). If I wanted to play an MMO, i would play one on my 2000$ comp, thank you very much. Personnaly, i am DMing exactly ONE game of 4th ed, and it's because old friends asked me too. I will be staying with 3.5 thank you very much.