I have one that is a little close (when I stand 10 feet away I don't notice it). I think part of this question is also would white Sash "modernize" my wood trim home OR look out of place? And even thought I'm "10 feet away" I know it doesn't "match" -- so that feels a bit off too

Are you referring to trim around the windows? Do you still have original wide solid wood trim? Just match the white of the vinyl - if you can take a sash to the paint shop that will help them get you as close a match as possible. Whites are all maddeningly different - hard for us to recommend anything. Keeping trim same as window sash helps the new vinyl blend in and be less noticeable... Then get a slightly darker, richer white for the walls (if that's what you want)

Our neighbors have black outside and white inside and is a beautiful modern home…..although it’s probably wood not vinyl. We wanted that look too, I got a bit confused when ordering. I thought just the just the interior grills and sashes would be black and the casing would be white. ( they are wood as well)… not great for dogs nails!) Oops! The whole things were black. Could have been an awful mistake, but it looks good against our light walls. We did get vinyl in the bathrooms white on the interior and black exterior. It works well with our tile… got that right. Here’s a picture of the black windows from inside…it caused sleepless nights a first. I like it now, but we put in temporary blinds( that just stick in with command strips… because we needed privacy and found out that if we screwed holes in the windows, it voided our warranty!) I’ve seen it done in a lot of houses so I don’t think you will be unhappy with the results. I would recommend you look closely at samples of the vinyl windows very closely. I went to see them ( our builder had a sub he recommended). Look at the workmanship closely. The samples I saw were a bit disappointing… there was sloppy silicone caulk and gaps where there shouldn’t have been…we ended up using jeld wen windows instead. Pretty expensive though. Good luck.

+1. Job is a bit larger than one would think. To do it correctly, you'd want to drop the surrounding siding panels, remove the j-channel, remove the old vent, install new one, reinstall j-channel (new if the new part is different size), and then reinstall the surrounding siding, Given that it looks to be in good shape, I'd agree with the thought to replace or retrofit a wind baffle.