Whereas I mostly agree with Wars as to why TS is what it is, I disagree with his approach.
Like he said, TS is great because there is great talent here in many different aspects - There are great forum administrators/mods, there are great authors, great amount of help for the newer members, and everyone remains dedicated. Tankspot is just as well known as any of the other "bigger sites" (mmo-champion, elitist jerks, etc). TS is actually my second homepage tab. I reference TS every day, literally.
Now, where can we grow from that? There are a lot of different ways, as you have mentioned. This is not unlike leading anything else - businesses, raids, guilds, or sport teams - there has to be a time to define what TS is now, and where it wants to be. TS leadership must ask themselves, "Do we want to grow to reach more people" while knowing that there is a higher chance of getting "those kinds" of people who have no respect for others, but on the other hand becoming much larger and respected a lot higher......Or leadership needs to ask "Do we want to continue to focus on tanks, and just have small branches for everyone else?"
I started coming to TS when I first was learning how to tank two years ago. I came from tanking to healing, and now I'm going back to healing. I am trying very hard to keep the healing aspect of the website alive, and have been trying to get a name for myself in the healing community of TS. I say this because I am in huge favor to growing to a bigger aspect of people, and I say if there is a risk of getting "those kind of people", bring it. I trust the admin team here, and I know that if the community grows, so will the leadership team. I hope that someday I could make that team, but even if I can't, I know that the healing admins would do a great job to ensure the values and integrity of TS stays the same.
That was a tangent, and thus did not answer your question directly. I think the best way to grow as a community to reach other people would be to make a central website that has posted information and videos. Home page offers a portal to Movies, Guild And/or Raid Management, Tanks, DPS, Healers. Sub-domains are amazing for something like that. And would require a lot of maintenance, but I feel that the community and leadership team could make that work.
As far as the healing aspect would go, there will be a better understanding that it's not just for tanks (Usually on my server if I suggest to a healer to go check out Tankspot, I get laughed at), which would bring out a bigger variety of healers, different levels of experienced players and authors, and finally give healers a "home" like Tankspot offers their tanks for dedicated, specific information.
I am, and will continue to be, a huge supporter of TS. I am not a donor, because I literally make enough cash to pay my bills and play wow through gift cards from friends and family, as I go through college. Whether we get a more dedicated "part" of TS for healing or not, I know it will be right for the site and thankful for what I have.
"If the tank dies, it's the healers fault. If the healer dies, it's the tanks fault. If the dps dies, it's their own damn fault!"