I like the idea of Victoria Newman and Billy Abbott together, since they are the heirs to the fortunes of the two most prominent families in town. If Y&R were to decide once and for all to make them an "endgame couple"--a pairing that avoids the endless break-up/make-up cycles of most couples on this show--then they would be able to take on the role of the next-generation power couple. They would create a core family of their own, separate from their immediate relatives but still connected via all the brothers, sisters, aunts, uncles, etc. The show needs to create a new generation of strong couples and families because folks like Braeden, Scott, and Bergman aren't going to be around forever. Having middle-aged characters ready to take up the mantle of the seniors when/if they leave will make the transition a lot easier. It is also a good tool for the show to have at least one couple who can be counted on to stay together, since that creates loyalty in the viewers who feel they can count on the show not to screw up at least one coupling.
Just because V&B might be earmarked as "patriarch/matriarch in training" does not mean they have to tone them down or make them less flawed. ATWT had Bob and Kim as their town patriarch/matriarch, but also had Tom and Margo as their "patriarch/matriarch in training" (Tom being Bob's son). Their lives were never boring, and they even had occasional break-ups, but they always found their way back together. It was pretty much assumed they would--no writer was foolish enough to break them up permanently.