I'm enjoying this event, mostly.
1. I like the two daily specials. One of my challenges with the daily special system in general is that often I log on, see that I'm not interested in the daily special, and I don't play the event that day, or often for any day except 2 or 3 of the 20+ days. The two track daily specials increase the chance I care on a given day.
2. The regenerating tournament tickets give me a reason to participate every day, too. Well done.
3. The event is too random; the chance for a prolonged losing or win streak due to good or bad luck in the tournament is high. If losing the previous match increased the chance of winning the next one, that would be completely a-thematic, but I think would make the game less frustrating and move it toward the kind of randomness we see in the Archaeology event. More thematic solutions: Losing gets you one free player card; or, the options are not just win or lose, they include "draw" which gets you some lesser reward.
4. Too random, part two -- having the 50 stickers available as a daily reward, especially the first, day, would seem to have a huge effect on how well you advance through the tournament afterward. That's a single too-large luck swing. Reducing the number of stickers awarded greatly would help, moving them later in the event where 50 stickers has less of an impact would help, taking the idea of awarding stickers as a reward entirely and substituting something else would help too.
5. I like the double ended reward with a chain in between.
6. The rewards inflation doesn't seem too out of control with this event, although I'm wondering about the possibility of the two ends with lots of extensions between them, combined with Blue Galaxy. The Train was lovely / OP that way, and this could be too.