Great, so I'll try to throw out a few more ideas:
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off the top of my head, Ultima 7 also had the ability to stack crates or chairs on top of each other, and then climb on them. This could add even more depth to the game (and again would require redoing everything with mouse drag and drop)
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In Ultima 7 the best thing was to move an object and discover a secret object behind it. For example, you moved a chair and saw a lever behind it, which opened a secret wall. How did you know that you had to move that chair among 1000 chairs? Maybe you found a hint somewhere else in the world, even far away, that said there was a secret in that house.
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as I said, inside the drawers/chests you saw many objects stacked on top of each other, and you had to move one to reveal (for example) a key underneath it.
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the way you set up the game has a lot of potential because, since there is a huge quantity of all objects, you could theoretically have puzzles that are both realistic AND not too easy. Which is very difficult in a normal adventure game where there are few objects and therefore it is easy to brute force.
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since I understand that you don't have time to make a complete game, then why don't you just make an engine, an editor, with which you allow someone else who has more time to make a complete game? This editor could also be a commercial project!
you could also experiment with exteriors, not only interiors.