As I leveled in my 30's I, like too many others, disregarded my destiny quest as an inconvienience. But at higher levels, 40, 50 and 60 I began to do them, and the message I want to get across is that they are VERY important. Every ten levels you get a new step of your destiny quest, you'll want to do these for many reasons 1) You get an items such as a ring or some other useful item (They have very decent stats), 2) You gain a ton of experience (over half a level doing the level 60 step at 62), and 3) PERMANENT increases to your characters stats. That's right, every time you complete a step after 40 you'll go back to Shakur and be told to "remember some of your past", in this you can choose to have an increased mana pool, increases mana regen or increased magic rating (damage). I chose mana regen the first time then +to rating the 2nd two times and noticed a difference in the range of damage my spells can cause :)
I hope this helped some of you and you go out and do these soon after you're eligdable. Some of the destiny quests have some "hard to get past" steps if you aren't looking close enough, so if you have any questions about a particular stage of the destiny quest post a comment on this post and I'll reply as soon as I can (it's better to post here rather than e-mail me because other people with the same problem can just read the solution here).