No offense but you're thinking in WWE terms and scale.
In 1984 Vince McMahon used "Madison Avenue" type of media blitzes to get the WWF and Hulk Hogan known to EVERYBODY. Vince simply advertised EVERYWHERE, places and media no other promoter had thought of before (to be...fair, earlier promoters just advertised to wrestling fans; Vince advertised to the world because he wants the world to buy his merchandise and PPVs). With Hulk Hogan as the poster boy for this new thing Vince called "sports entertainment", the world was there for Vince and Hogan to conquer. Vince put the Hogan name and face, and the WWF logo, everywhere, all over TV, in magazines, and just about every piece of merchandise you can possibly think of. And it worked. The whole world learned about the WWF and Hulk Hogan, and Vince increased his audience exponentially.
The WWF and Hulk Hogan were new, caught on with the "mainstream", and became phenomenons.
It didn't happen overnight, though. It took a LOT of hard work, a LOT of money, and a lot of years to achieve the success they did. And for a decade now, the WWE has operated unopposed, the 800-pound gorilla, monopolizing the business, and keeping all other "competitors" down and small.
Vince's propaganda has trained the wrestling fans (especially the "mainstream" fans) to consider everything else inferior and not worth their attention or money, to the point that when anything new (or different) does try to break out it is met with scorn, derision, and hate from Vince's audience.
TNA has been struggling for 8 years to penetrate the market owned and monopolized by Vince McMahon and the WWE. TNA HAS succeeded in "getting in", but at a VERY small scale. Most WWE fans know OF TNA, but comparatively few of them actually consider it "worth watching", thanks to Vince's propaganda telling them it's a laughable little "rasslin" company, and considerable ignorance from a lot of Vince's audience about what TNA really is.
Hogan HAS made a difference in TNA. While there hasn't been a huge jump in the ratings (yet), the brand awareness has been raised considerably. We see a much larger percentage of TNA-related questions in this section since Hogan arrived than there were before. TNA has been able to sign bigger stars recently because of the Hogan name attached to TNA. TNA gets talked about more often and more regularly throughout the internet since Hogan arrived.
TNA is not (and may never be) at the level of the WWE as far as number of fans, money generated, merchandise sales, etc. TNA is not and may never be as big a company as the WWE, but to say TNA isn't popular is misleading.
TNA IS popular and IS a successful company and wrestling promotion. Just not at the scale the WWE is. A comparison could be: Target is a popular retail chain, but Wal-Mart is bigger and gets more customers simply because they have more stores and the Wal-Mart brand name. So it is with TNA. The WWE is bigger because of brand-recognition and more "stores" (TV shows) but TNA has it's customers (audience), as well. Both are successful and popular, but at very different scales. TNA might one day grow to WWE proportions but that day is still far away.
WQ: I think so. Vince has surprised us with some recent entries, so I think Chyna will eventually get in. Vince's Hall Of Fame is supposed to honor those who have made "significant contributions" to the wrestling business. And Chyna certainly qualifies.
WQ2: Indifferent. I was never a huge Batista fan, but he was good for the WWE while he was there, engaging in some memorable feuds. If he wants to come back, I wouldn't object.