I'm pretty new to designer games. I really enjoyed all the gateway games, partly because I can complete a game in less than an hour. Does anyone have a recommendation for a moderately hard-hard game that is less than an hour? Most of the games in the OP seem to take about 2 hours. Also, after playing a few games, I realized I hate deck building games like Dominion.
I would suggest Betrayal at house on the hill. Game length and difficulty can vary, but it's usually been around 40 minutes for me. Most importantly though, it's a shit ton of fun.
The main premise of the game is everyone is exploring an old mansion for a reason unknown. As you play the game, you will explore the mansion by flipping over room tiles and getting items, encountering events, or revealing Omen cards. Eventually, depending on the omen card you reveal in a certain room, "The Haunting" occurs, which reveals the real reason why you're there and who the traitor is. One player will then be pitted against everyone else with 50 different scenarios that can happen involving such things as: Ghost brides, Cannibals, Porcelain Dolls, Giant Bugs, The House sinking into hell, etc.