Ranked diamond league points issue

[Nales]

Got to Diamond 5, still gaining 30 points per win and losing 20 points per loss (same as platinum).
First, I thought points gain / loss at diamond was 15, so it's odd that I have a "bonus" of -5 in case of loss.
But most importantly, why do I still have a bonus after reaching diamond? Sure, I reached diamond 2 in S1 so my MMR must be high, but I thought the bonus would stop at diamond 5, top. I find it rather unfair that high MMR players have such a huge advantage at this level of ranking. Is this really intended?

[Kujo]

The actual gain/loss numbers were posted here. Remember that Diamond is not the top: there is Master above it. And the way they described season 2 ranked was that the best players would all be up in master, so it makes sense that there's still a bonus possible all the way through Diamond.

[Nales]

Ah, they changed the number of points in solo diamond since their official post about it.
I thought the idea was more to let you catch up faster on your S1 rank, or something. Alright, so your points gain directly depends on your current MMR. This system makes sense somewhat, but it feels rather redundant: since your MMR already rises and drops as you win and lose, why have a ranking and points system on top of that?

[Kujo]

If matchmaking is working perfectly, then most people are winning 50%. That means most people will get to Platinum if they play enough. Bronze through Platinum are more of an indication of how much ranked you have played, and not how awesome you are. Getting to diamond or Master means either your win rate is > 50% or that your MMR is high enough that you get bonus points. This gives everyone goals they can make progress towards while leaving the top ranks for the best players to fight over. I don't know if that's the devs' thinking, but I like it.