Improve my Gig is the primary section for that kind of thing so it’s already available. A few people are kind of self appointed to help in IMG so that’s nice. When I feel like throwing out some tips for individual newbies, I go to IMG. Welcome is mainly for self-intro, but it’s not moderated heavily.
Intros/Welcome is a catch-all area and similar to Conversations except it’s intended for people new to Fiverrr or the forum and is Fiverr-centric. It’s always been broad: http://forum.fiverr.com/t/about-the-welcome-category
There is no rule against asking for help.in the welcome area as long as they don’t add links. Help requests are just more likely to be answered in IMG.
The only reason Welcome/Intros is there is because adding a new top category that newcomers see immediately helped massively in reducing the “how do I” posts in Tips for Sellers. It worked except for a random post here and there. You can mute the category if you prefer, but it’s mostly working as intended. I don’t know why another newbie/help category would be needed.