I agree it is easy enough with Excel, I have no idea how to code. I have been removing numbers, dashes etc too. I find scanning quickly and not miss anything while scrolling in Namedrop involves just way too much eye hand coordination and definitely is cramp inducing. I like the excel pages for just a simple click to replace all the domains in view with the next ones and amazed how many times faster it has been.
Filtering for .com only, then "does not contain .com" after in a second run through is a great way to prioritize and keep the desiterd search image clear and distraction-free.
If you want to filter by domain length, use the following in the Custom AutoFlter drop down, set to Equals and ????.com for 4 letters, as each ? represents a single letter.