i love it when innovations in a new application are carried over to older tools. zsh seems especially suitable for that. it soaks up good ideas like a sponge and finds a way to integrate them. on the other hand it does make zsh feel kind of overwhelming at times in terms of options available.
my favorite part besides autosuggestions is the way history works, not incremental but i can type out a search term, and then start searching up and down the history.
incremental search is always irritating me by showing me irrelevant stuff while i am still typing, which i find distracting because i have to process it while at the same time focusing on typing the search term right.
now if only i could also have multiple search terms...
(i also prefer the fish syntax, but that is more of a matter of taste and getting used to)