Hints

I don't see a reason why transients (even real transients like dialog boxes) should not be organized or decorated differently--in fact, I think that's usually a good idea. The thing I insist on is that I retain the ability to arbitrarily move, size, raise and lower them (including the often-denied privilege of restacking a dialog window behind its parent, and independently minimizing parents and transients), regardless of decoration or initial position.

I do see many cases where the transient windows *themselves* are often a bad idea, but that's application misdesign that a window manager can't fix.

I've used truly hintless window managers (ones that don't move the keyboard focus from parent to transient and place the transient randomly, so I have to aim at the appropriate window with the mouse cursor for every single transient) and hintful window managers (ones that respect all of the hints to the letter and even impose restrictions of their own). If these were the only choices (thankfully they're not) then I'd pick the hintless WM, because it's at least possible to sensibly arrange windows with the hintless WM, even if I have to do a lot of extra work manually.