Just relaying my experience in my '30 Tudor...I put a 3:54 in my '30 Tudor back in 1980 when I did it... in the later 80's. I added a Ryan overdrive and decided to leave the 3:54 and see how it did. I thought at the time if it was underpowered I would switch back to the 3:78...never did, but Actually.. it has done well... although.. on my 2nd engine, admittedly my previous .125 overbore had more power than my current .030 engine. which runs a Snyder HC head. Babbitted engine, virtually nill leakage after 15 years with this engine. (Rich Falucca rbld)
The 3.54 does well for general driving... and when on the highway the ryan is great. It is not as quiet as the Mitchell ( I think they were just coming out about that time) but it does well. I have had no problems with it... and have had several trips to Colorado, climbed Pikes Peak, Canada, and countless other trips and states including the recent Blue Ridge Pkway tour. It might be geared a little tall but it sure makes for nice highway cruising and gear splitting when needed, and of course have lower gears when needed as well. Everything mechanical is up to snuff so I don't have to worry about poor front end or braking...
I cruise on the highway about 55-60..... of course have had much faster.. and did 75+ around Indy and texas motor speedway when there for meets.
I'm an advocate for keeping them stock... with the exception of the Snyder HC head and an overdrive.... It makes them cruise a little easier in today's traffic.. and is not as hard on the engine and components. In addition they drive a little more comfortably on the interstate and other higher speed roads. Knowing your car, it's speed/power range, and driving smartly is key... and as Brent indicated you use your overdrive when applicable.
Larry S.