I like STEM too, but I don't really create much suitable content for it... but I can see how it would do really well. I like FOODIE and LOTUS, but I'm not sure of they have all that much of a big-picture plan.
so far, I have only used the POB front end for comments, but I will undoubtedly create posts with it as well... perhaps when the ecency-based front end is fully operational and running. The main reason I use PeakD is because I can save drafts and templates and such, and I almost never write an entire post from start to finish in one sitting... and these hive.blog "clones" used as tribal front ends are just too austere for my liking. That was one of the original attractions of LeoFinance... they built a highly usable and feature rich front end from the ground up.