Use what you want, make what you want. But if you go w/extractors, have a prepared statement ready every time you show off your personal prize.
You'll be asked over and over as to why extractors on such a beautiful gun and not ejectors.
The answer is simple of course,,because you wanted it that way and beyond that it's none of anyones business,,,but the question will be a forever one. Kind of like why did you dye your hair green.
Everyone has said 'I'll never sell this gun',,but that doesn't always hold true. In those cases, the ejector upgrade will not make the buyers flinch and say 'extractors??' when they open it for the first time.
Definetly a value point. Like 'em or not, they are just about to be expected on a high grade or upgrade. That doesn't make them a better practical choice of course.
If practicality was in play, so would an Worthington Special for a base gun. Maybe it is,,I completely redid an Enders (Royal?)Special 20ga once and came out w/a fine shooter!.
Some guns allow the ejectors to be disabled, springs removed, and they still work as an extractor gun. A possibility, but perhaps you don't want nor care to deal with it.
I've upgraded more than a few extractor guns just because I liked the gun to start with. All of the above came with it,,but I still liked the gun. I eventually sold them, but not because I didn't like them. I just like to make others.
I've built plenty of ejector gun projects too.
They sell much easier (I know that's not supposed to be in play).
Fox and Ithaca ejectors are about the most trouble free US guns I can think of off hand. I don't think 21 is in play here.
LC Smith can be a real pain. Parker are not actually too bad from a maint and problem point, but if they do have problems, it's much harder to get parts than the others,,and they are a complicated compared to the others.
I don't care for SST,but they've provided lots of income over the years fixing them. DT or at best a simple SNS trigger as on the Ithaca is OK. DT's is my vote.
Lots of Belgian, German,Austrian shotguns around of excellent quality, many with no names, that would lend themselves to an upgrade. They are usually simple strong boxlocks, many w/ejectors if you want them, many w/o.
16 and 20ga guns are not that uncommon and the quality can be many times over what a US made shotgun is from the same pre-War era. Something to look at also.
Keep short chambers, abrupt forcing cones in mind with any early gun, US or Foreign.
Have fun. Make what you want, You Deserve It... Thank You!
