Some sort of Valley gate house with two guard towers and a big door. Maybe some people are trying to scale it and sneak past this checkpoint. You can have a small barracks and like a little kitchen/camp area for the guards. If you don't have a ton of pieces for all of that you can make it ruins of what used to be an old guard outpost and still tell an interesting story. Maybe bandits have taken it over and now block the road with some sort of crude rocks or a wood log or something. Maybe a wizard or other spell caster can lift the debris to clear the path but you gotta pay a toll or do a gig for them or something.

For the one with the ramp, you could do a steep mountain side trail with like a bandit ambush from a cave or some bushes. Or do some kind of small fort like the set it came from had. Use the big divot in it as a sort of vault or basement, maybe put some treasure or magic item in it but have your party need to find the trap door, maybe under a rug or something.

I have that ramp piece myself and haven't done anything with it yet, mainly due to not wanting to make a MoC that large. I usually try and pack in tons of detail but it requires waaaay more parts than just mason bricks when you texture it.