Not a bad rendering of this common theme. A certain part of theme entries, in this case, the last half, can be put with another word, in this case CHAIR (64A: Head, as a committee … or a word that can follow the ends of 16-, 29-, 36-, 47-, and 61-Across) to make a compound word. So we get different chairs, and they all work well, in that they are all common chairs, and the theme entries are all common, normal things.
In the fill we get symmetrical crosswordese with RUER (13A: Regretful one) and ERTE (66A: Onetime Harper's Bazaar illustrator), which is strangely satisfying. ELBE (51A: River to the North Sea) and ATOP (25A: Perched on) are also symmetrical, but those two are maybe not quite so crosswordsy. Balancing off the standard fare, though, we have SLOUGH (52A: Cast (off) and STEPPE (22A: Treeless plain), and many of the falling sevens are quite nice. NUTCASE (2D: Crackpot), SPLASHY (40D: Ostentatious), and NEBULAE (41D: Interstellar clouds), to name a few.
Overall, this played slightly harder than some Mondays, and it was also a bit more interesting. What more can we ask of a Monday?