Hi! I agree these are interesting suggestions.
I think #1 can be simulated by setting up a character as a crate with a speed of 0 that you would move to a designated tile with the Move Character function. This would need to be entirely scripted though, and not ideal for real sokoban-like games. I've used this for my game The Egg.
#2 is easily achieved by using Remove Entity, or Put Entity to move the model out of view, or Play Animation to change the model's state to an animation with an empty frame. I've made extensive use of the third solution in The Egg to make platforms appear and disappear.
#3 could probably be simulated with lots of work, but would clearly require a whole new system to actually work for puzzle games.
I think #4 could also be simulated on a limited height by using timing, vertical animations and the Put Player function. Maybe using very steep stairs could also do the trick if set up properly, I guess that would require some experimentation. But yeah, proper ladders would be cool.
To sum up, at the moment, if you need #1, #3 or #4 for specific parts of your game, you can use some heavy scripting to give the illusion of such systems, this will need more development to work in a simple and user-friendly way.
Personally, I'd love to see such features in the future, they would sure blend well with RPGiaB's tiled-based approach.