I'll also speak up in favor of the iPhone 6s Plus. I came from an iPhone 6 and wanted the larger screen. I knew after about 2 months or so with the 6 that I had made a mistake in not getting the 6 Plus, but decided to wait until the next series came out. I'm totally happy with everything about my 6s Plus, battery life, smoothness, speed size, weight (and I always put my iPhones in cases which of course adds to the weight).
I'll now do my little happy dance with my 6s Plus.
Consider yourself extremely lucky that you didn't get the 6+. The 6S+ is the first big-screened iPhone worth anyone's time.