1. Command key requirement keeps you from accidentally deleting files
2. I actually really like Enter to rename now that I’m used to it. Renaming is a common operation in many instances.
3. Yes, space key opens quick view. It works with most common file types and is very fast. I don’t see a problem here.
4. This is a good point. The answer used to be Cover Flow but they unfortunately got rid of that very nice feature.
5. The home folder is not commonly used in their UI paradigm.
6. I’m not sure I’ve seen this behavior.
7. This is a good point.
I’d agree that “Finder is just horrible to use for someone who expects Linux- or Windows-like behaviors.” Once you’ve learned it, though, it’s mostly fine and, in my opinion, a bit better overall than Windows Explorer.
Yes, it could be improved. They really need a better cover flow replacement for browsing a folder of images or documents, for example. And they clearly haven’t been making much of an effort over the past few years to improve Finder beyond minor tweaks here and there. But it does its job overall, and long-time users (like myself) will miss features like Enter-to-rename if they adjust them to match the conventions in other operating systems.
There are also alternative file managers for Mac OS like Commander One and Path Finder for people who want more features.