The ability to ignore votes from other instances using an allow list. The ability to ignore votes in communities from unsubscribed accounts.
I see that your not talking about a Lemmy instance but a ui of a Lemmy instance. I think the biggest improvement from a UI perspective is button placement and confirmation messages for actions.
For instance, separate the delete post button from the edit post button and have a confirmation message for deleting a post so mistaken button presses aren’t permanently unrecoverable.