Earlier quoted context omitted.
Magit gets a lot of deserved love on the internet, but I think abo-abo (the author of hydra, which you listed) is quietly leading a kind of revolution in emacs usage. His trifecta of packages lispy (edit at the speed of thought in lisps), swiper/ivy (a simple and powerful interface to every facet of your editor), and hydra are the main reasons I use emacs over vim.
lispy - I use smartparens, it have mostly similar feature set. Smartparens advantage over paredit (and it seems lispy) is that it focuses on giving good support for editing parantheses groups in any language. E.g. you can use it to edit C++ expressions. See my post: https://kozikow.com/2016/06/18/smartparens-emacs-package-is-... swiper/ivy - I am already hardly locked in into helm. Even if some competing packages are…
Check out the simple overview[1], and maybe some demos[2].
[1] https://www.youtube.com/watch?v=BverGxP41cE [2] https://github.com/abo-abo/lispy#demos
swiper/helm: this is more of a personal choice, I agree. Having given both a fair shake, I find ivy more easily extensible, and I prefer the simpler look. As for the community support, there has yet to be something for only helm that I've missed in the various counsel functions.