Always happy to see new events! My thoughts on this one:
Win in X turns or more is just generally overused as an objective, and forces players to artificially drag out games. So many things in this game are time-consuming already (token generation animations, etc.) that if we can find ways to win quickly, we shouldn't be punished for it!
It's especially egregious here, because the same node that wants you to win slowly is also giving you a free 2/2 token creature every turn. Just doing the math, if both players literally cast ZERO cards the entire match, the detective tokens alone would do 130 damage by turn 11, meaning you can literally cast nothing an entire fight and still win too quickly! That does technically make it a difficult objective, but maybe not difficult in the way that's intended. I'm gonna go out on a limb here and suggest that players enjoy casting cards and doing stuff with their deck -- not being forced to blow up or disable our own token stack and do as little as possible with our own deck so as not to miss an objective.
It's not ranked, so maybe players will (like me, after two fights on that node) all just ignore that particular optional objective, but in that case...doesn't that still just make it a badly-chosen optional objective?
Also, this might be a bug, or just bad wording, but: both event supports have a trigger for "When a Clue support is destroyed during your turn" but seem to only trigger when you destroy your own Clue supports during your turn. Destroying an opponent's Clue with e.g. Demolish doesn't seem to trigger either event support, and destroying an opponent's Clue by swap on your turn seems like it can still trigger the_ opponent's_ event support.
What he said^
I don't think there's any reason for 'Win in X or more turns' to be put into any more new events. It just leads to durdling.
I suppose that, since many creature kill spells in the game only work on opposing creatures in recent years, you might have to put a dedicated card into your deck for this event to kill your own stack of Detectives, but I wouldn't say that constitutes making the objective 'difficult', merely 'time consuming'.
Now might be a good time to bring up the fact that we, the players, do not like the fact that most creature kill spells now only affect opposing creatures.
This is, like too many things in the game, a lazy workaround, caused by the fact that Greg's AI will often target his own creatures with kill spells, setting him back and helping you out. In the past, with every set that came out, the devs would neglect to set the single flag in the code on these cards that told Greg whether to point the spell at his or our creatures (not technically the most complex decision to make!), we'd post a bug thread about it, it would get fixed on that one, individual card (this thread contains a (non-comprehensive) list of old bug threads like this), and then the problem would inevitably show up again in the next set.
Then, one day, one bright spark on the dev team figured out that he could save himself this minimal amount of work, and all it would cost us, the players, is a lot of extremely useful and convenient functionality. See... you might think that wanting to shoot your own creatures is something a human player would never want to do, but it turns out that many of the games we play in MTGPQ are game with objectives, and we often find ourselves in a position where, if we don't kill our own creatures, we will kill Greg before we've completed the objectives, losing ourselves ribbons in the event and maybe dropping hundreds of places down the leaderboard (funnily enough, Oktagon had a lazy workaround for this problem too... they drastically cut the prizes offered during coalition events so players wouldn't mind so much if they plummeted down the leaderboard due to a single lost objective, or an app crash)
I tried different ways to get the opponent to discard two cards when destroying his Clue tokens but none of them actually triggered the permasupport to get him to discard. Seems like a bug to me.
Overall, I didn't enjoy playing the Event.
As for the "win in X or more turns", this is probably the rare case when it's good that the secondary objectives put together give as many ribbons as the main objective (to win). I did 6 fights at the bottom node (60 ribbons total) and instead of 3 fights at the top node with full objectives (= 30 ribbons) I did 4 fights without the "win in X or more turns" objective (= 32 ribbons). If the objectives were all worth 5 ribbons, and the top reward was available at the 135 ribbons (same 9 fights with full objectives, but now worth 15 ribbons each), you'd need 45 ribbons from the top node (3 * 15), but in that case you'd need to do 2 extra fights instead of just 1.
Also, playing the bottom node felt like playing against the pre-nerf PMA AJani. Plus you can create Detective tokens more than once per turn, if you get extra swaps either from 5-matches, or from card effects.
Aside from the big issue where the Suspect side support didn't work at all, I think that this event would work fine if they reduced the amount of turns required on the first node to be 8 or 10. As noted above, you could cast zero cards and still win in 11 turns unless your opponents deck has blockers or removal. You shouldn't have to rely on your randomly selected opponent to make your objectives achievable.