Whitetail deer are not huge animals. Nor are they particularly tough skinned. So anything above a .243 should work well enough. (yeah, I know there are people who hunt deer with a .223, but not me)
As for action, I think the Ruger No. 1 is the best. Being a single shot, you lose about 4 inches of overall length, while keeping the same barrel length.
Anyone else have an opinion?
As always, it isn't what you're hunting ... it's WHERE you're hunting.
If you hunt in the northwoods of the midwest - as I've done - a .30-.30 is sufficient because you'll never take a shot over 75 yards. However, the deer can be rather large (175 - 225 lbs), so the increased kill power is necessary.
If you hunt them in Texas - where the deer about the size of a big dog - a .243 would be good enough.
In Colorado - where I hunt now - a .308 (my current favorite) is appropriate because most shots are a greater distance and the deer are much larger than Texas. (The last mule deer I killed was about 280 yards). Of course, to be honest, you are usually hunting elk at the same time.