I can see some points, just curious if there's something I'm missing. Have not gone THAT far in team theorycrafting, really, just haven't observed the same Rozuel hype as there was a bit of Ruel hype.
Both:
• Are 2.25/56.25/2.25
• Cannot activate their LS's themselves
• Have their respective Chinese as fantastic subs
• Unbindable
• Double SBR
• 7c

Rozuel:
• Can clear binds
• Makes hearts with her active for her crappy RCV, though the active is kind of random regardless
• Has considerably higher HP, but less RCV
• Leilans all the way (*if you're using Leilans, you still need a wood-sub monster – AAres?)

Ruel:
• Less HP, more attack
• Has a TPA
• Makes her LS attack orbs with her active
• RMeiMei helps make up for Ruel's lower HP, AND covers the dark subatt for activating the LS

Is the active pretty much the reason people like Ruel better? I feel like Rozuel could still do just fine, and being able to clear binds would be plenty useful. But there may be something more that a more in-depth look at subs would show, maybe... On the face of them, though, I feel like they're not that far apart. Rozuel may have a bit less RCV because her own is 0 (though the difference in RLeilan's vs RMeiMei's pretty much covers that, really), but hypered I feel like it's still plenty.
Not necessarily going to use them, since I only have one of each between my two accounts – just curious!