Tom mentioned after my initial challenge post that they'd actually changed the rules for how tshirts are given out this time around. I went on a mission today to figure out exactly what changed. It turns out that the number of tshirts they've been giving out has been on quite the decline (61 to 23 to 14) which is why the challenges this time around felt more attainable. Needing to farm 1/8th the currency to buy all the uniques is a pretty big deal!
There is a catch, however. They made it a lot easier to complete all the challenges for sure and they don't want to have to give away thousands of shirts if it turned out the challenges were way too easy. So they put a cap on it. The first 50 people to complete all the challenges will get a tshirt and that is it in terms of shirts. They're also awarding some microtransaction rewards for people who manage to get 5 challenges done and for everyone who gets all 8 done.
If getting a silver or gold halo to wear is something that really interests you then there's that extra little thing thrown in to encourage you to get some challenges done. I don't much care for the halos myself. And while I was feeling like I could probably put in a good try on getting all 8 challenges done I have serious doubts about my ability to be one of the first 50 to get it done. Getting all the masters to max level felt like it was going to be hard but maybe possible depending on how fast the rep gains accelerate as you level them up. But if that's the challenge that takes the longest (and I think it will be) then it's going to come down to who is more heavily involved in getting quests from other people. And that's probably not going to be me. I'm happy to do my own dailies, and I'm happy to do dailies in a group with people I know, and I'll pick up quests as I'm playing. But I don't think I want to be hanging out in a chat channel with random people and trying to worm my way into their quests too.
There doesn't seem to be a leaderboard for challenge completion that I could see but it is an indicator on the normal leveling ladders for the two leagues. I took a look and there are a couple people who already have 6 challenges done. I have one. *sigh* Both of the people with 6 done are missing the challenges for the masters and leveling the classes. So, yeah, leveling the masters is going to be the gatekeeper for sure.
Eh, I'm not giving up yet, but earlier I'd thought it was looking pretty plausible and now... Not so much.