Finder file dialogue very restricted - any way to enhance it?
You indicate in comments that you need a free solution.

There's no free solution to do what you want currently. macOS does not come with a preference settings that enhanced that specific context menu.

If you're able to program yourself, it should be possible to add extra menu items to the menu. This should be possible free of cost, but will ofcourse take time.

As others have recommend, there's commercial solution such as "Default Folder X" available.

In your comments you also express that you find not only the file picker dialog, but also the standard Finder to be very limiting for you. In this case, you could consider using an alternative to Finder.

Some good examples of alternatives are "Path Finder 9" and "Commander One". The first costs a bit, while the latter is free in the standard version.