I believe this has been suggested before.
Grouping doors
This feature will allow you to place selected movables into a group, so all the movables will be linked as one (if one movable of the group is linked to a trigger, the group itself is linked to said trigger, if a movable of the group moves, it will move the entire group with it). Grouped movables will only be able to be moved to grouped regions. Grouping will be a tickbox when you select two or more movables (Shortcut for movable and region grouping is pressing G while selecting multiple movables or regions, ungrouping is U). Grouped movables will only be able to move to grouped regions (see below).
Grouping regions
Similar to the movable grouping, this will allow you to place selected regions into a group, so all the regions will be linked as one (share same trigger to initiate, share same activation initiator). Behaving similarly like grouped movables, if a region is moved, the entire group moves with it. Only grouped movables will be able to initiate grouped region actions. If a grouped region is set to initiate with a USE panel, the biggest region inside the group will have the USE panel on it. Grouping will be a tickbox when you select two or more movables (Shortcut for region and movable grouping is pressing G while selecting multiple regions or movables, ungrouping is U).
I feel like this would be way more convenient for mapmakers who make custom vehicles using colored doors and shit rather than just wasting minutes of your life setting movables and regions one by one.