Not to mention the terrain generator of the past (which I always felt had little use, personally) if retooled to work with the new bricks, could create massive, unprecedented landscapes within seconds of clicking a button.
I mean, really think about that. Your server could have a completely unique landscape to build on. I mean, this is like taking the best aspect of Minecraft, the best aspect of Roblox (their new dynamic lighting) and then combining that with the already tried and true gameplay of Blockland.
So what you lose a few crappy maps? I'll admit, the bedroom was fun, but it never made my experience better. I know that as a veteran member, whenever we wanted to do serious building (whether it be sets for Block Wars or cities or DMs) we 99% of the time did them on a slate for complete control over the build. To say that we're really losing anything is, in reality, merely a small annoyance.
I have been pro V21 since I first heard about it, and I was still pro V21 when I heard we were losing terrains and interiors. And Iv'e been here for five years. Bisjac for more. Sure we can claim nostalgia about it, but then when all of us old cigarettes are for it, then I don't see why we can't all be for it.