The biggest problem with the old system was that it created a very steep hill. To go from no payout to $0.02 was a pain in the ass. Even with a dozen minnow votes, you were still stuck at zero. You had to have a whale or dolphin friend to get into the payment portion of the curve.
And, a problem we still have is that the distribution of SP looks like an exponential curve. So, exponential curve X exponential curve created a steep rise, but also a steep drop off.
Yeah, that was a steep hill to climb! I think curation guilds helped with that - they made the tail of the distribution curve much longer. But at the same time, they distributed a lot of Rshares, which made everyone else's vote worth less. The guilds could find a lot of the good posts, but not all of them. Today, Steemit is far more popular, and the work of curation guilds wouldn't go very far considering the gigantic increase in the number of daily posts.