Shia have a more centralised authority on fiqh and religious matters (Insofar as those are separate matters). While calling an ayatollah or a marja a "pope" is misleading, they still form a recognised and recognisable source of religious rulings.

Also theres different holidays they stand slightly differently while praying and there's a difference in when prayers are made iirc.

There's also some stuff that's unique to various shia sects that's different from sunni practises. Like using a prayer stone is a twelver thing.