It sounds like you want vim features. But vi compatibility mode is probably not consistent with these. Mapping f-keys should work fine in a GUI vim, but in a terminal F-keys may depend on configuring the terminal. You don't have to use syntastic if it doesn't work right for you, you can just use individual checker plugins or set makeprg and use :make. Mapping auto-complete to tab depends on not having multiple plugins fighting over the key. Most of this is a matter of particular plugins, not vim itself.
Right, I want some of the vim features, mainly plugins. I don't enable vi compatibility, it isn't even remotely vi compatible and it just breaks stuff. I want syntastic, that's the primary motivation for trying to get vim working. I just want it to be helpful instead of irritating. No plugins are messing with tab, I am just trying to get it to work using a normal mapping.
