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And so many questions:
1. You can go back any time and solve your remainig quests, when you are stronger. All but the main story line quests are voluntary, but good for experience to level up. And you do NOT always know from the start, whether it is main quest relevant, or not. (This is true until you sound the gong to become the divine - that's a point of no return, with still some things to be done)
Do accept all quests, that way, they get registered in your quest log. If you don't remember details, check the conversation log - it has all conversations with all NPCs you ever made.
2. At some point yes, but seldom, and not necessary - you will not share experience!
3. Yep, that's how it is - in this instance carry & cash (not the other way round as usual)
4. A good one for bow could be the skill "poison weapon
5. No contradiction here, mate!
6. Simply do NOT go in there before you're higher level, and then get all the experience you can from it. No other reason for it, except you will see the three again later...
