I don't know why there is all this hate on this system. In my opinion (am I allowed to use that word on GD?) the elo system was stagnant, allowed for no real improvement over time. This would then create the illusion of "Elo Hell". With the league system, some may fall divisions, HOWEVER, the ability to climb divisions is much greater than it would be to stay in a division for an entire season.
How exactly does the league system benefit players more than the old elo system?: This system is a system allows for a player to actually be able to improve, and rise through their division, and helps find their proper skill level more efficiently than the old system. It also creates (while some may think this is a false sense) a sense of progress. This makes playing ranked, as well as wanting to improve MUCH easier. For example. you start playing ranked in Bronze division III. After winning 5 games and losing 2, you are at 67 points. This gives the player the feeling that they are closer to advancing, and will promote better, more careful play versus a player feeling they are stuck with a number that doesn't seem to be improving.
Why is there so much hate and criticism on this system?: It is new, and a lot of people don't understand it. The gain/loss IS in fact balanced, and working as intended. Yegg has responded to these issues, especially the topic of league point clamping in division I, which should ease people into understanding how the system works. One thing people need to understand, is that MMR plays a large factor into the League Point gain/loss. Once people understand that once their MMR is in check for their division and that they will then be gaining/losing at proper proportions, the system makes a lot more sense.
Overall: This system is no easy way out. It is not a free diamond. However, it DOES allow for players to develop and improve to the level they belong a lot easier. I for one, have dropped a division since starting, but I feel it is actually helping me realize what I am doing wrong/need to do (such as playing champions I don't feel confident with, due to lack of experience) and I have seen greater success in solo queue. Those who hate the system, I am not here to say "QQ moar" or "you're just bad" because I am not one to tell you what you are to enjoy, and I am certainly not one to talk about skill level, but what I can say, is that it is very easy to see how the new league system greatly benefits player development and ranked play as a whole.
tl;dr : league system is not bad, and working as intended, and once understood, greatly benefits player improvement and development, while not putting players at skill levels they do not belong.
THANKS FOR READING!!!!!!!!!