I'd say has the lion share because it has a better experience. Many folks DO NOT want the old experience from Live. Various threads and arguments on the suggestion forums about difficulty and old-school versus new school COH experience also bares that out. They prefer the path Homecoming is on: Aka a more streamlined approach to COH that doesn't waste the player's time with time sink nonsense we had from live (which was necessary for a subscription game).
On the other hand they also don't want the insane (but admittedly fun for a short period of time) sandbox feeling of Cake, where you can sneeze and everything falls over (With the changes that team has done the word "difficulty" is not even a serious discussion on that server).
Costume pieces are nice, Full on sandbox COH is also nice (for a short period of time), better play experience over all trumps that. That's why HC KEPT the population all this time. Regardless of who set what server up first.