Yeah 'Plov' there was a well known conversion for the dove & the Heron for that matter 'Reily conversions' to convert the power-plants to more modern units, Lyc's to be exact. The original Dove with the old Queens had 400 gee gee's if I recall as did the Lyc IO720 flat 8 so HP didn't change. The Heron had IO540's with around 275HP (don't quote me just a ruff guess) much like the AC50 planes.
In fact the other old Dove I used to drive VH NBM had a more modern fin on it also, prick of a thing to track straight down the Rwy 'till the airflow increased over it, never did find out what it came off but looked much like a Cessna type fin/rudder & even the main cabin door opened outward needing a ladder to get in & out of the cabin unlike the Dove in the painting (VHABM) which had an airstair door.
Lots of Mods over the years on the old Doves, they flew the best of any airframe I ever had the pleasure to drive
'Centy' just saw yr post now. I'll go find the official report for a read.
The old Dove didn't need flaps for T/Off unless the strip was very short or had other factors that looked threatening so unless any Flt manual stipulated flaps for T/off I would never consider them at all for the very reason/s you mention above.
Once full flap was selected 40 deg's I think it was for Ldg you where going to do just that land, no going around in a Dove unless you have lots of height avail. I always considered once you where below 500 ft you where going down one way or another.
Wmk2