A few different questions.
1.) you aren’t missing anything by making your thief Asuran, so just play the race you like.
2.) sword/pistol with a focus on power and precision, and dagger/dagger with condition damage as a focus both work really well for leveling. sword/pistol uses black powder and pistol whip to blind/evade tank enemies, while dagger/dagger conditions uses death blossom and the caltrops utility to bleed enemies to death while kiting them. really though any weapon set you like works for leveling. those two are just considered the most efficient. as far as trait builds, if you are using power based attacks critical strikes is a good tree, and for conditions trickery. survivability comes from acrobatics and/or shadow arts. at first pick traits based on the stats you want, then at later levels focus on the major and minor traits you want.
3.) I cant think of any videos for PvE right now, but the people on the forums are quite helpful. just let us know if you have any questions we can help answer. some advice though, time your dodges, thieves cant take hits well at all. signet of malice works well while leveling if you pull big groups, as well as in combination with caltrops and dagger storm. shadow refuge is a really nice ability, so pick it up when you can. you can use it to harvest resource nodes or open chests while ignoring the big baddies that tend to guard the more valuable stuff.
Gungnir Aurus – 80 Guardian
[AUX] Isle of Janthir
Two weapon sets have simple concepts. Sword/pistol lets you blind enemies with smoke while you hit them with a sword. Pistol/dagger lets you shoot things with a pistol from range after crippling them with a dagger. There’s more you can find out about these weapon sets as you level up too. Power is probably the best stat to pick and you don’t need much else until you have your own favorite play style.
1. Im Sylvarian thief atm, for character model i think human still get a better look, then Sylvari, 3rd ill pick Asura. Because you can make your Asura a full pitch-black skin + white/golden shining eyes, which is a potent coolness. But now, if theres some race change feature, ill change to Asura and make my pitch-black assassin