Fish Shell
I've been using Fish Shell for a long time. Before that I used ZSH with oh-my-zsh on top. As much as I like Fish, it's different enough that I sometimes get stung by little terminal and scripting differences. I'm thinking of going back to ZSH and (possibly oh-my-zsh). That idea feels both comforting (for using the common/default option) and unsettling (for needing to layer a bunch of oh-my-zsh stuff on it).