@dearest - my lists always have to have a number ending in 5 or 0 (50 or 85 names, for example), and I always try to keep them within 20 names of each other, but I’ve successfully gotten it to 50 for each! 
XD I’m not sure I’m going to allow myself the luxury (torment) of adding one more name if it turns out my boys list has 64 names, but I totally see your point!
Congratulations on getting it down to fifty! That’s impressive!
I’m going through the ‘up for consideration’ part of my boys list right now. The rest of the boys have been narrowed down to 48, so I’m hoping to find 2, 7 or 12 names among those… 
And I just pushed a whole lot of word names into a collective maybe pile at the bottom of the list where I might forget they exist. Progress at last!
If I’m doing some serious list clean up I record myself saying the name. If the name still appeals after I hear it said a few times and it doesn’t make me cringe or just feel ‘off’ it’ll probably stick around a while.
I can usually cut my list down to four or five names that way.
I’m not sure it would get my list down to four or five but it’s definitely a good idea.
I also ask my hubby to read out names. It definitely cut [name_m]Cedric[/name_m] off my top list as I only like [name_m]Said[/name_m]-ric and he says See-dric and he doesn’t hear the difference so it would be a continuous uphill battle. (One we might come back to later but for now it’s be put on the GP list).
There’s also the Starbucks test (or any restaurant that calls out names).