New mechanics wishlist item I just thought of that I've not seen(/noticed) mentioned before... You know how constructions can sit top edge to opposite bottom edge:
# (side view, '#'s being built walls, the upper one
#### built from/supported by the top of this layer)
..?
If sideways rams are implemented (e.g. in horizontally moving walls) how about something you can attach to such blocks (or use to attach to such blocks) so that you can release them (irreversibly) or lower them (otherwise) into the gap below in a vertical direction.
Multiple uses come to mind, including 'proper' floodgates. Not that I don't like the current floodgates, but these could be lowered/forced from the level above, if there's room.
On the other hand, this suggestion could be viewed as an attempt to circumnavigate some of the (fun!) logistic restrictions of the current setup. So, I might accept and amendment of this idea to being able to haul a wall segment vertically [/i]up[/i]. (Again, need space to move into... Either that or a (limited amount of?) structure on top that isn't connected to anything else, for a massive masterpiece of displacement... Hmmm... That would have potential, too... Caverns full of oscillating megaconstructions, even a way of implementing non-axle mechanical logic by certain bits of a structure actually have room to move up/down into a space sometimes occupied/blocked by another bit of movable structure.)