Can be changed in SmartGit 18.1 in the "Low-level Properties" section of the preferences.

Do you mean environment variable support in the Command input field?

If you just have 1 commit selected, then the Changes view always shows the older part left and the newer part right. If 2 commits have been selected, the Changes view's title shows the IDs in the correct order.

This is available since ages. Just stage the parts of the file in the Changes view (non-compact display) or even better using the Index Editor, then commit.

Currently, the Output view uses a tree control which does not support word-wrapping.

This is not a common task for 99% of the Git users.

These 3 rows should indicate a pile of files.