Having played this game for the fourth time earlier tonight I think I can start to give a useful opinion of the game. The group I play with at my FLGS tends to be on the larger side with an average of 6 players. I have personally played in games with group sizes of four, six and eight and other games were played over the weekend that I did not participate in.
The mechanics are fairly sound and easy to learn. I like the uniquenesss of the items, not knowing the possible outcomes of spells or conditions, having 2 actions to choose from, always getting to roll at least one die and the ramped up difficulty after the ease of winning Arkham Horror (with the exception of new Yig, other Arkham Nights Ancients Ones are fun).
The only problem with the mechanics of the game that I've notived so far is the scaling for larger groups. The two games played with four ended in a win and a close loss, so far the larger groups have not fared so well. In the first game with eight players it took three hours just to complete the first mystery, we were all new and learning the rules, but three hours is a long time for one third of a game. With tonight's game of six players we failed to advance the first mystery even once in the two and a half hours before the doom track advanced to 0 and we lost to Shub. Bad rolling played a part here in that of the three attempts made to advance the first mystery all failed, but we lost overall because a few bad rolls and unlucky monster draws seemed to have much more of a snowball effect than in the four player games and most of the game was spent trying to pass the rumors and play catch up with monsters.
While I want to play more games with varying group sizes to be sure, my initial impression is that the game works best with four players, is functional but with a large difficulty increase at six and nearly unwinnable with eight. Given the scaling mechanic I would not want to play with a group of five or seven investigators and would be heistant but willing to try three investigators, I have no interest in one player board games.
My biggest disappointments in the game components was the inclusion of only four ancient ones and twelve investigators. Given the ancient one mechanics I can understand why it was limited to four, but for as often as I like to play games of this sort, I like more diversity in my fight for survival. The investigator pool being limited as a play mechanic I can also understand, but after much Arkham play we like to deal out a few random investigators and choose from what we get. With only twelve we can't even deal out two to each player when eight are at the table, not a big deal for most groups but for my group it's something we'll consider when it comes to choosing the game of the night.
One suggestion in the rulebook is to not read the possible outcomes to the player before they roll the dice and then only read off the results of the check. While I like the idea in theory, mechanically it can lead to very bad choices being made. One example being gate checks, on one check a player failed the first check, but decided to spend his clue to pass to reroll a die and then passed the check. Unfortuantely for him succeeding on the first check led to a second check with which he now had only one die to roll to close the gate as that was his lowest skill, had he not spent his clue and chosen to fail the initial check he could have made a skill check with his highest skill, had four dice plus the clue and still had a chance to close the gate. To make things more frustrating on the next turn he was required to spend the clue he no longer had just to have a chance to close the gate. Other times players have not spent clues on a reroll only to discover that it was not possible to close the gate if they did not pass the first check, but would have had they known. Given the difficulty in gaining clues in this game and how often they are spent rather than used for rerolls I lean toward a compromise of let me know if I'm wasting resources or hurting myself by spending one or more clues to try to pass the check. You lose a bit of setting but also a lot of frustration.
Overall I really like the game so far and would recommend it to people that like Arkham Horror or Lovecraft in general and think it would make a good addition to almost any game library. More games will be required to see if our larger groups were just epicly unlucky or if there really is a mechanical issue with the game that should be addressed. I'm looking forward to having a second win soon or at least another close loss.