When I bought my restored 1930 Town Sedan many years ago, I did several things that are on many's no-no list: a Mitchell OD, a Snyder 5.5 head, a V-8 clutch and pressure plate, lightened flywheel, a 6v alternator, real halogen headlights, LED taillights, and a concealed turn signal kit. Everything else is pretty much stock, and without looking real close it looks very stock, and also drives pretty much that way. But I did want a nice Model A that I could drive anywhere, anytime here in S. Calif., including on the freeway or on fast surface streets.
I have driven on many tours and also drive it at least 4 times a week, and I don't regret any of these improvements....I did not plan on showing my car, but wanted one that I felt comfortable and safe in.
As to the alternator and halogen lights....before I went that route, I tried using the brighter regular bulbs and they were better, but not even close to the halogen bulbs. My lights actually light up the road now. I also have had no issues with my battery either...it is doing just fine.
As with all of these items, it is a very personal choice as to what to change, or leave completely stock...the folks that don't want an alternator probably would never have an overdrive either.