Date 34 vs DJ36 vs OP34 vs OP36 - substantial differences?

[R332]

I am shopping for a classic and timeless daily wear stainless Rolex for my wife that is mid-sized with a smooth bezel on the Oyster bracelet. I would prefer if it had a slight sporty edge to it since she already owns a formal attire watch. If R made a 36mm Sub I would buy that but they don't and she finds the YM too flashy.

Looking over the men's and ladies options there are four models that seem appropriate.

OP34
OP36
Date34
DJ36

Other than the later two having the date feature and the obvious (small) size difference are there any major reasons to choose one model over the other? Resale value isn't a consideration because she will own the watch forever.

I understand the DJ36 and OP36 are probably the newest members of this group and until today I wasn't even aware of the Date34.

Any advice would be appreciated!