I only play slots and after 30 minutes i usually get bored no matter if Ioosing or winning. However 30 minutes could have a huge effect your balance if you play volatile slots 
30 minutes of playing slot games is more than enough to impact your account balance whether positive or negative, this is a game that depends largely on luck, so the less you play it the better, and this of course, still depends on the wagering amounts. However, if you are now bored within that time, I congratulate you, after all, you will not be stressing yourself too much about the money that could be wasted playing slots game for too long.You're right, 30 minutes is More than enough just like as you said earlier because one can easily lose a huge amount of money within the space of 30 minutes in slot game, which is why spending a lot of our time in slot game is not good. However, I think you're right when you said that it depends on the wagering amount. Of course most people can decide to stake with a little amount but even as that we are not supposed to spend more than 30 minutes in playing slot game.