We can all agree that Ren and Cube were close to neck and neck on SOC
BUT
Ren was third in the group for recognizable personalities behind Cube and Eazy,
and fourth in this category to people who knew Dre was on the beats.
Don't forget, "Express Yourself" put Dre front and center even though in the song he mentions that he didn't write it.

Now let's go chronologically:
88 - Straight Outta Compton
88 - Eazy Duz It
89 - No One Can Do It Better
90 - Amerikkkaz Most Wanted
91 - Death Certificate
91 - Efil4zaggin
92 - The Predator (with Cubes biggest hit to date)
92 - The Chronic
93 - It's On 187um Killa

And where does Ren fit into all of this?
Kizz My Black Azz in 92 and Shock of the Hour in 93.

Now how in the hell can your fourth most charismatic member be expected to be noticed when the market is flooded by his former teammates?
SOC set the template, but Eazy and DOC were allowed to run with it, not Ren. Add in the fact that the West Coast adopted a lot of this sound quickly and now the whole NWA posse has to be a step ahead so that their lane doesn't get outplayed by their followers.
So Cube drops and completely changes the landscape from a sonic perspective. Sure PE were big, but it was a coup for a West Coast artist to come so East Coast, even if the particular East Coast sound he was using was an extreme and not the norm.
So what does Ren do? Knowing he prolly can't make it on his own, he wisely stays with the group. The only problem is the group is splintering; had Dre stuck around maybe Ren would be sitting pretty and Cube would have been a successful Syd Barrett.
That doesn't happen.
Dre leaves and now he too blows up with a different sound (the arguments for his following others need not be brought up here) and not only does he change the sound he has a new extremely charismatic rapper with him in Snoop.
So where does that leave Ren?
His group is dead and everybody except Yella is having amazing success by being extremists (Eazy) or trailblazers (Cube and Dre)
Ren's only hope was to go hard, and while he certainly did he didn't have the crossover appeal as his former compatriots.

IF Eazy wasn't a cult figure and
IF Cube hadn't taken off and
IF Dre's attempts at a new sound hadn't become the new standard
we could reasonably assume that NWA would have reformed sooner than later and still touring today with Ren in the fold.

But that didn't happen.

If the NWA was the Frat Pack,
Ren would be David Koechner.

<----

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http://www.youtube.com/watch?v=EeM89CITvMc

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