6.88 didn't crush 6.87's balance, to use the image. It tuned several values that should make for an even better balance.
Bigger changes can be expected after The International 2016, at the latest when Abyssal Underlord finally gets released.
@Alex V. Sharp: Well, that only mean that over 95% of the heroes are viable. And that's for the competitive scene.
On another note, I just can't see a day where the updates will just.. stop. I don't know, even if gets all balanced, if a new item or hero is added everything will need to change again