I always enjoy the discussions on derivative species as they relate to modern hybrids. I have tectorum (triste) which seems to have the pointed leaves and goes dark certain seasons, though to a lesser degree than the two varieties you mentioned. If that long leaved black you spoke of is the same one you posted a picture of a while back, it's one of my favorites of the seedlings you've shown online.
I'm raising a batch of bee seed from 'Watermark King' this year, at a time that was in my top five, but my collection has grown steadily since then. Most of those seedlings have color already.
I have found myself favoring both slender and wide leaves in every major color category, I have a pastel pink seedling from 'Lilac Time' x 'Hordubal' that has extra sharp leaves I am considering releasing. 'Lilac Time' was a great parent, but in crosses to other wulfenii types the variation from it is less obvious. I had someone in my garden ask if one of my favorite seedlings from 'Lilac Time' x 'Silverine' was 'Lilac Time', I found that a bit discouraging as it is very similar to the mother plant, grows better though. I was considering releasing that one but now I'm not so sure. Others from that cross have more interesting forms, a few have wider leaves, but none are as big or offset as well as the lookalike. The family isn't particularly large which might be the problem, all are nice but no big standouts, there's much more variation in my 'Lilac Time' x 'Grey Lady' group though none of those have such thick wax.
'Lilac Time' is the only parent I've used every bloom season for the last three years, it's such a fantastic plant that it's hard to beat.