Maybe have a setting on a modelled control panel that determines what type of shielding you have.

one could be exterior when using flight panel if you add damage to it. And interior could protect the tardis from being blown up which would be a good feature for DMU since there is a lot of bridging and breaking. Something like this could prevent that.

For the advanced regeneration maybe if the interior is too damaged it could kick you out for a certain amount of time and when that time is up you come back to a custom generated interior? 

Eg: Coral tardis with classic roundels like war. Or Toyota with Coral Roundels

I don't know if this has been suggested before but i thought of it after rewatching the 11th hour to help through the pain i go through

It (Tardis interior regeneration) has been suggested, many times. It was also a feature in the mod in the past, but was removed because it caused more problems than it solved. Implemented differently, it could perhaps work, but in it's plain form, it's a broken feature. Players could farm blocks for one, and a regenerating interior has to account for customization.

What i'm trying to say is, Yes i do know it has been in the game before.

But maybe implement it differently as i mentioned having it kick people out of the Tardis when it is too damaged and have a force field sort of thing around the exterior so it can't be bridged to or broken into

I suggest that when the tardis is too damaged, you get a panel to choose a predetermined background ... like what appears when entering a new TARDIS. This means that the current entrance door is replaced by the new TARDIS.