Edit plus is my preferred text editor.
Most of the features you did not find are actually already there:
Make a selection:
Edit > Format > line comment
-- or --
Right Click > Format > line comment
It would be nice to be able to open all files meeting some criteria at once.
Search > Find in files (Alt + s , i)
According to the help, it can, but I have never managed to get it to work...
Search and Replace across open files
I use this all the time
open up the find replace tool (ctrl + h) and check All open files (alt + o)
Find and replace within a selection is even better for template like functionality.