First off, welcome to Middle-earth!
A similar question was asked a while back and I provided my low-effort blue line build there. Obviously if you've just started you're not going to have nearly so many trait points, so don't stress too much about which points from red are most important, etc. And as I said in that post, if you're playing solo there's no right or wrong way to play, just what works for you - so feel free to play around a bit and see what you prefer. This is just what I use, but you might want to go for some more heals, or for Pathfinder, or whatever. As pointed out in that thread, the True Shot trait for Penetrating Shot debuff is also a good one, but I just leave it out for solo play because things are dead too fast for me to want to bother with a mitigation debuff. So you see, everything is kind of optional when you're playing solo, that's the fun part
If you want some stronger advice though, there are some traits in both blue and red that are, well, a little useless. So I would advise against just maxing out every trait in blue and then going to red. For example, Bow of the Righteous, Moving Target, Strength of the Earth, Improved Intent Concentration, all IMO are wastes of trait points - but don't listen to me, read the tooltips, try 'em out and decide for yourself! If you love them, then go for them
As for being able to manage quests and such on your own, you shouldn't have any problems, hunter is one of the most survivable classes, even for new players. In blue line, your power comes from being able to kite effectively, so make sure you have that down, but it sounds like you do already! Do bear in mind though that blue line is lower in DPS than red, so it is going to take a little bit longer to kill mobs.
You're correct that you should focus on Agility and Vitality, there are a couple of other stats you want to look out for: critical rating, physical mastery rating, and mitigations (mostly tactical mitigation). Critical rating is as it sounds, it increases your chances of scoring a critical hit, and the magnitude that your crits/devs will hit for. Physical mastery just straight up increases the damage of your skills. Mitigations give you protection from different types of damage (physical is from, well, physical damage like swords, bows, etc., tactical is from "magic" damage like Shadow, Lightning, Frost, etc., as well as Fire and Acid damage types). You can get a decent physical mitigation rating just from the armour value of your gear, but tact mit is a bit trickier, hence why it's worth being more aware of it.
Agility is useful because it increases your crit and PM, but there are traits and gear items that can increase those stats on their own. Vitality is useful as it boosts your morale and your tactical mitigation. You can also get tactical mitigation from virtues, which I recommend: I use Fidelity and Tolerance on my hunter (and in fact on all my other toons as well). As for other virtues, I would go with Determination, Valour, and Confidence (or Wit if you prefer). As for racial traits, high elves get an out-of-combat rez which could come in handy seeing as you don't have one otherwise, and there's a run speed boost which I *believe* stacks with Find the Path, so might be worth getting that too.
Hope this helps, am happy to help with any other questions you might have