I used fish for a couple years but switched back to zsh. I found the incompatibilities with bash/zsh to be annoying at times and finally just decided to do the "When in Rome do as the Romans" do thing and adopt zsh.
If anybody else is using zsh-autosuggestions, it's really worth looking into configuring it rather than using it out of the box. It exposes some pretty cool options. It was sub-par out of box in comparison to fish, but after some tweaking I like it better. You can do things like ignore history based completions on certain commands (like git, I don't need my last commit message popping up)