FWIWFM, I typically find dipoles fiendishly difficult to set up properly in a room. Get it wrong and you'll get lousy imaging, tubby bass or no bass, and comb filter effects that mess up the entire sound stage. Full-range 'stats that go to 50 Hz or below do not sound "lean" to me but of course you can (not) hear that missing bottom octave or two. In addition to dealing with the speaker placement and room, getting the subs properly phase-aligned at the crossover point is something a lot of folk fail to consider IME. I would estimate that when subs are added that is the issue that leads to "lean" or "thin" sound in most installs I have heard.
Room treatment can solve a lot of the upper bass on up frequency response issues, but if not done with great care leads to a loss of the reflected content so prized by most dipole owners. My room is dead, dead, dead -- any ambiance comes from the source and not the room. It works because the room is small, the speakers are large (Magnepan, not ML, but much the same issue), and the system is pretty clean (though orders of magnitude beneath WBF standards, natch).
IMO, FWIWFM, IME, YMMV, my 0.000001 cents, etc. - Don