Have the ability to recharge a partially depleted item like the Bat-Pack instead of only being able to recharge it when it is completely flat. I'm guessing this is dealt with using the damage counter on the entity so calculating the remaining charge shouldn't be too difficult.
One thing I have found that can be challenging (depending on available space and layout) is the top/bottom output from an MFE. My suggestion is this;
By default, an MFE would have the same output logic it currently uses (top or bottom) but right clicking on any of the exposed faces of the MFE would change that face to the output block and would be identified in a similar way the HV identifies it's high/standard voltage output. I realise this may present issues where an MFE has cables attached to all six faces (ie which one is the output?) but this could be dealt with again in a similar fashion to the HV transformer where the output cable (first block only) has the red sparkle animation.
Right clicking a 'set' output face would return the MFE to it's default state.
What about a toggle instead? You don't want to be running around in the dark holding Ctrl all the time!