that's (if i'm reading your ? correctly) all things which reside inside of the 'admin' section of WP, rather than in the 'front end', I think that what you're trying to acomplish can only be done by editing core files within the wp-admin folder (which I wouldn't recommend doing because future updates/upgrades won't be possible without creating a mess).
the only other approach I can think of off the top of my head would be to create a plugin (or maybe one already exists, you're not feeling smart, but I'm feeling lazy, so I don't feel like checking my notes or the wp-plugins.net site) which controls what's displayed on the write post page based on a user's 'access level', this way you're not editing any core files, but can hide things you don't want users to see, I'm assuming/guessing that you only want to hide those things from some authors/users, not someone like the site admin/yourself, etc). If i feel 'unlazy' later, I'll check both my notes and the existing plugins, then post an update.
...c
(ps. what you're looking to change shouldn't be theme dependent since it's in admin.css and wp-admin folders, rather than themes/default (eg 'Kubrick' as you mentioned).
cielogrande
