Nice, tough Friday puzzle! That NW corner took me at least half the time today, and I had to put it down and come back to it several times before finally taking out "Jean Arp" and putting in the alternate HANSARP. Very tricky! Then, somehow, OVERTHEMOON (1A: Thrilled) (B) came clear. Did you notice that "tickled pink" fits into those squares exactly? I sure did. It was my first entry and I was loath to take it out.
Also in that corner, the "ones" part of TIPSONESHAT is routinely maligned by crossword reviewers, and RESOD (4D: Maintain, in a way, as a lawn) is not only a weak word, but I feel the clue is almost misleading, as it's more of a renewal than a maintenance chore, isn't it? VAINER and OCTANT are also less-than-ideal. In fact, the whole corner is a bit MESSY, so I don't feel so bad about spending so much time up there.
The SE, on the other hand, is quite nice. We've got AGEOFREASON (55A: Period following the Renaissance), the bowling combo of SPARE and BOWLASTRIKE, and the Huygens-ready LEWD (51D: Blue). I also enjoyed THESIS (43D: Argument) and FLAGON (41D: Mead holder).
Elsewhere, there's the nice "Healthy/Unhealthy" pairing of FIT and ILL, the lovely word AEOLIAN (29A: Windblown) (but I'm guessing that E will be a tough get for many), and I'm always happy to see my NERD friend AMES in the grid.
Overall, kind of a mixed bag, but I like the challenge, and I like more than I dislike. You?