Pictures should be expanded by default on the post page because they provide important context for the post, so anyone who comments should have seen it first anyway.

It is already possible to limit search to a single community, but a search bar above the post list would be faster and more convenient.

This concept screenshot shows how it could be done.

Currently, URLs to posts have this format:

lemmy.ml/post/[number]

I suggest changing it to this so people can see the community immediately in shared URLs:

lemmy.ml/c/[community-name]/[post-number]