I’ve not done anything with lighted switches, but I agree, the S2 is a great flashlight. I have one that I’ve changed the reflector to smooth (from Simon) and added a Qlite driver (from Intl-Outdoors) and it’s fantastic.
I’ve never been able to see much difference between the S3 and the S2, so I’ve stayed with S2’s and S3’s (with the exception of a single S2 UV). I have a lot of Convoy lights and I’ve never been disappointed in a single one, ever.
Pro tip - Never, ever scan a hotel room with your UV S2+ (especially when your wife is with you!). Some stones are better left unturned.