So, while typing out my questions, I found out there is only a 1,000 character limit to the post, so I'm going to have to cut this up into multiple posts, because i have several questions, and I'd like to keep them all in one thread, so please pardon my multi-post.
Here we go.
First, a friend that got me back into Final Fantasy 14, keeps advising me to never do quests outside of my main story quest, and that I should just focus on my hunting log, doing dungeons, and the main story quest. His reasoning is that it "Makes it easier to level your alternate classes later" Honestly, I'm not so sure how I feel about this, or if it's even accurate, so I figured I'd ask, should I be avoiding doing all the side missions? It feels weird to play an MMORPG, where doing all the quests is a bad idea.