I haven't bought this game yet, and I'm trying to decide on it.
If you desire a mid-weight game that is still easy enough to get casual gamers quickly into it but has enough "meat" to be interesting for more experienced gamers I would highly recommend it. I like to think of it as a little bit easier "version" of Concordia. Nevertheless, the card play mechanism is different and very unique. I played it for the first time last year and it has been for me one of the most pleasant surprises.
After reading the rules and knowing that I'll likely be playing a lot of 2-player games
It plays pretty well with 2 players but I think it really shines with 4 to 5.
You take a 3 point penalty for choosing a bewitched role. Now, given that there are 10 roles and each round 3 become bewitched in a 2-player game, that leaves you 4 out of only 7 'safe' roles to choose for each round. That's more than half.
That's the beauty of it: Even with 5 players and no bewitched cards there are no "safe" roles. It all depends on correctly guessing the cards of the other players and the turn order.
I'm wondering, how often (on avarage) would you want to choose a bewitched role, if at all?
Impossible to say as that can vary wildly. You may have one game without choosing even one and another it would make sense to do it 3 to 4 times.
Or in other words: does the bewitched rule simply reduce the role pool for each round, or is paying 3 points for a certain action a real strategic consideration?
There is more long-term strategy involved than you may think. The towers further away from the castle give you more points. So you choosing a "bewitched" witch that allows you to move closer to those towers may make strategic sense. Choosing a "bewitched" weather fairy to get a cloud out of the way could be very beneficial. Picking a "bewitched" gatherer that gives you much needed potions can make a lot of sense.
Reading the map correctly and choosing the roles accordingly while not being too predictable is the key to the game.