"Slots have cycles of winning combinations. You can win by observing these cycles and entering during a winning part of the cycle."
This is a myth, as slots work on the basis of fair, random numbers. The casino advantage is hidden in the mathematics of the game, and there is absolutely no need to complicate the whole system with any kind of cycle.
In fact, it is possible to observe winning tides and losing tides. But that is just a result of natural randomness and those tides are not predictable.
"Slots are programmed not to pay out after a big win and to pay out more when they are full of money".
This is a myth that probably stems from the days of standalone slots that paid out directly to the winning player. But it was a myth then just as it is now. If you won more money than the slot machine could pay out, the casino staff pays the rest.
Modern slot machines are connected to a central server and all winnings are paid out by the casino staff, so there is no need to keep in mind the amount of money in bitcoin slot machines. Random numbers work very well and this myth is invalid.
"Auto play features pay out less than manually clicking the spin button"
This myth makes no sense to those who know how online slots work. The mathematics of the game remain the same, and the random numbers remain fair whether you use the auto play feature or the spin button.