The format bar has lots of things, that are usually evil in a word processing scenario (i.e. font selection and stuff), but not the one thing that is a really good thing to have in word processing: preset formats. To use format presets I have to click though a 4-level submenu and if I don’t manage to stay withing a menu item while moving the mouse pointer to the next submenu, the submenu is replaced by another item’s submenu. This kind of kills the idea of having predefine formats, when they are difficult to apply. Please implement a preset format drop down in the format bar (and, possibly, a way to remove other items from that bar).
By the way: I’m on Linux, but I’m totally willing to pay you guys. Scrivener rocks!
One thing to make clear is that our presets are not quite like styles in word processors you may have used in the past. With true styles, where you can dictate the look of assigned text via a central definition, it indeed does make sense to avoid using inline formatting as much as possible, entirely if you can. With format presets, you are basically just bundling these formatting commands into a convenient macro. So really you aren’t replacing the standard formatting tools, just making it easier to switch from something specific like a block quote back to body text styling without having to change a half dozen things.
That all said, you should be able to add the presets button to your Format Bar (and remove whatever you want from it). Have you gone into the Tools/Customize Toolbars menu? I haven’t checked on Linux, maybe that doesn’t work, but it should be.