It's hard to sense how much of vi is in vim, having only ever used vim. But I've never been very happy with vim, even though I've used it for 15 years. Maybe I need to find a "vim, the good parts (aka vi)" book.
A couple of examples. In Spacemacs, the screen regularly goes blank for a while. Or if I have a file open in Spacemacs, close its window, then rename it in the OS, then reopen it in Spacemacs (by double-clicking it in Finder) it reopens it with it's old name. I'm sure there's a way to avoid this, but the fact that it happens in the first place is the issue.
As for the file rename issue, certainly if that's part of your workflow, it's helpful to figure out why it happens. I suspect it's due to the way filesystems work on Linux /Unix.