Hmmm... I hadn't made that connection - that the powers are mystically tied to the demon who engendered them - but I guess it makes sense in retrospect. Likewise no more demon-killing powers once Ruby died at the end of season 4. Okay, I guess I can get behind that.
It's my first re-watch since original broadcast, so it's entirely possible I'm rusty on some details.
Sam's ability to harness powers were seeded by Azazel (not Ruby), and his normal random vision induced power seemed directly keyed to Azazel (each and every use) and seemed fueled by the living blood of Azazel.
Once Azazel died, no generic abilities. And unlike all most of the other "Special" kids Sam never tried to master those visions. The only exception was in Salvation where he tries to dig deeper into the vision. But he never initiated them.
Ruby taught Sam two things. That his powers are fueled by blood. And that means consumption of normal demonic blood (Which is like putting gas in his fuel tank) it seemed to stay there until he used it all up (or that blood was drained from him).
But the normal demons Sam feed off of didn't seem to have any connection on when that demon died. Azazel seems to be the only one that occurs with and frankly since Azazel is a vastly different or more powerful demon then the generic black eyed ones that makes sense to have it having a different impact.
The other thing Ruby taught him is how to harness that power into specific skill sets. And she seemed to focus on ones that had very real specific uses in both getting Sam ready to kill Lilith and the ability to protect himself from demons who want to kill him.
Ruby's life had no direct impact on Sam's ability to harness power. Her death simply cut off his most available source of demon blood.