Hi Tom,
I think it all comes down to the (hear-say) fact that RC chooses the best features / tie points first. So you are probably stuck with this behaviour as long as there is any significant amount of ideal surface left. Window frames like yours are notoriously difficult, especially when coated with a semi or full gloss paint, which almost any of them are.
Can you show some of the results you got?
I myself have come to terms that there are just some elements on buildings, where you cannot expect a perfec, or even any result at all. Just now I am struggling with a roof where there are some very smooth tiles between old decayed and mossy ones. Many of the smooth ones have holes in them, even though they are almost exclusively in the foreground, where the resolution is better than further away and also the angle is better. I was already at full length of my 9m pole, so nothing I could do to prevent this. But it also happened with much better angles at lower parts of the roof. I can’t explain it but it would take too long to optimize so I am either just going to leave it like that (as a natural restriction of the technique, like window panes) or brush it up a bit in IPS.
Also, this time I got a flaws in some window and door embrasures, since they are made of a rather homogenous artificial stone. So even though I took all the images at an angle to prevent that, and usually the resolution should have been fine, there are still issues like that which can throw a pebble in the clockworks. 
You can see that it’s exactly like your issue - no TPs at the embrasures (the black door is good enough) but plenty on the plaster. As you can see, I’ve tried CPs, but they are all fine as it is. It’s really only the lack of TPs on certain areas. Again, I am going to smooth this over in IPS by overlaying orthophotos at different levels, since the flaws are only on the outer edges.
Thinking about it, maybe raising the max repro error along with the preselector could aleviate that. But since I wouldn’t want to mess up the whole rest of the model, I would need to do it locally, which means quite a bit of additional work…