Guild Wars 2

To 1. . You can easy level a neco with all kind of weapons sets, just look for something that goes well together such as : dagger/warhorn axe/focus | staffscepter/dagger just to name two options. There are alot more options that are just the two i leveled my necros with.

To 2.: You should alway adjust your traits to your playstyle. If you decide to go for a condition orientated leveling buid then search for traids that benefit that playstyle. same goes for power build.
Condi example: http://en.gw2skills.net/editor/?fQAQBYCRqwzA9IXwFQM6BxYMJDA
Power example: http://gw2skills.net/editor/?fQAQRBHbhG2IjW6elmyG9eCRqQzA9YXqFnh6h7sOfIA

i used those without any problems.
Another option would be a borring minion master build which i will not list -.-

To3.: Necros can do everything they want, like any other class. It#s up to you to decide if u wanna do burst dps/ heal support/ play minion master / play with alot of wells or play with conditions or a mix of any of those options

To4. there is no best end game weapon set only best at for example power burst or conditions

I am just about to start gw2 again and this guide made the choice of profession very easy, thanks alot for that. #Amazing