I'm really missing Colour mapping tab in VFB. I understand that to have ability to adjust exposure settings in three different places can be somehow confusing for new users, but tone mapping controls in VFB was most convenient way for me.
This broken up exposure interface... I even reported it on Mantis (not three but four different places!), especially now with unsynced values in render settings and VFB tone mapping tab.
If it were up to me i would completely remove anything exposure wise from render settings. Move everything to camera modifier and tone mapping in VFB (with identical interface!). When rendering camera view camera modifier has precedence (if it were up to me you couldn't even render camera view without camera modifier), and when rendering non camera view tone mapping controls in VFB are used.
What if you need to override everything, you ask. Well that could be a problem, and we're back to render settings. But with a separate rollout that overrides both camera modifier and VFB (with some simple "override" check box and, again, identical interface!).
So it would be a simple chain, render settings > camera modifier > VFB tone tab.
But, that's just me, and what do i know about anything... :)