Well, the best advice might not appeal to you but it is really important for you: read every trait. And every skill. There were a lot of changes to some skills in mean time.
Isengard expansion means that you should know that the will is the main attribute for lore-master, but it doesn´t contribute as much tactical mastery as it used to be.
To the trait lines: you have three to choose and in selection screen you can immediately see some description of what you get once you chooce a line. Once you choose a line, you won´t be able to see the starting description (unless you respec).
Blue line: stronger pets
Red line: lightning strike has chance to hit the second time + slightly stronger felines
Yellow line: skill Proof of Will + bonus dmg on stunned enemy if hit by Burning Embers
Also, you can now save different builds, thus you can build one for solo play and one for group.
For group play, yellow line is the most important. There are a lot of debuffs and improvements for support role.
Red line is for dmg. One hidden mechanic is that you can upgrade burning embers dots with Gust of the Wind in the searing embers (stronger dot).
I mostly used to play a combination of yellow debuf and cc traits and red fire dmg traits
For solo, it is enough to choose red as primary line and then take Fire-/Frost-lore from yellow line. Around lvl 68 you probably don´t have too many skill points, so it is better to invest deeper in one line, because the other two cost 2 points instead of one.
If you are doing group content, then choose yellow as main. It is common that you do almost no damage since you have to keep up many buffs/debuffs + pet rotation (oh yes, you can summon pets in combat and they have then reset cds on their skills. So you can stack different pet debuffs).
Ich bin kein Deutscher, sorry für Grammatik.
English isn't my native language, sorry for mistakes.