Option to hide unused objects in inspector/debug view
Yes! There are several existing similar ideas, you can vote for them:
construct3.ideas.aha.io/ideas/C3-I-1591
construct3.ideas.aha.io/ideas/C3-I-1382
construct3.ideas.aha.io/ideas/C3-I-950
construct3.ideas.aha.io/ideas/C3-I-1442
Sibling relationship for Hierarchy
Edit hierarchy relationships at runtime
Isn't this already implemented?
On tile created event
I don't think this is needed. Also, since tilemaps can have many thousands or even millions of tiles, this event can be bad for performance.
Background brightness for Tilemaps, similar to the Sprite Editor
Not sure what you mean, what background brightness?
crop images project-wide
Why would you need to crop images on export? To remove unused transparent space? I think bulk-resizing all imaged in the project is a bad idea. This can potentially break lots of things in the game - collisions, image points, tilemaps, tiled backgrounds, effects etc.