Gold on the Junkyard
A good use of a small number of cards. The idea was very interesting, but I was confused about the rules. How does a player remove "the type of junk from the spot" when each card has four types of junk on it?
HAMLET
A solid, straight-forward game that makes good use of the limited number of cards. Some complex combinations and outcomes to remember, but they could be included on the cards (which at credit card size would be feasible) - or use a system like I described in this post. A person familiar with the game has a huge advantage, but it's the same for any similar game.
Micro Battle Arena
There’s a little bit of rock-paper-scissors in action, and both players would need to be very familiar with the rules to play it within 5 minutes. But I found the idea of head-to-head combat interesting, and could imagine the reveals being quite exciting.
Triad
I thought that unbalancing the sides is an excellent feature. With games this short it doesn't really matter if someone gets an 'unfair advantage'. A little bit complicated in the rules but, as mentioned above, some could be printed on the tokens. Movement would give clues as to the unit type - which adds to the strategy - but there is a possibility of mistakes/arguments by moving them while hidden.