but I believe it didn't handle the column pasting in the "brief" manner mentioned above (it apparently keeps the cursor in the same position as before you paste, which makes multiple pastes cumbersome)

Having communicated with UltraEdit's author a number of times in the past, I'll bet that if you asked him, he'd provide that as an option in the next upgrade (if it's not already). Perhaps there's an easy way to work around this, such as pressing a certain key combination to reposition the cursor after the paste.

I couldn’t find an option for “virtual space”,

In my version, which I admit is a few releases back, this option is called "Allow cursor positioning beyond line end". Works like a charm. If, after positioning the cursor in this empty space, you type a character, it pads that area with space.

nor could I find “smart tabs”.

Hmmm. You might be right about this one. My version has some tab options, but not a lot of them. I wonder if newer versions have more options. Just yesterday I was wishing I'd had some useful tab options, but ended up realizing that the file I was playing with was much better served by dropping it into Excel and mangling it that way.