Yep, I know exactly what you mean. It's been on our (correctly assumed
long) to-do list of probably a year now. However, to do it properly we
need to make some major structural changes to the way zoning works.
That's why this is taking so long.
I'd still like to point out that this is more or less an automation
feature (except the triangle lots). Everything you will be able to
make with poly-sided lots (more than 4 sides) you can already do now -
it just takes longer and is more annoying.
In any case, it will come. It's one of those "obvious" features.