I love this debut puzzle from Ms. Slovut. The six-entry, thematic progression of life from baby to ghost is a fresh new idea (or, I should say, at least I've never seen it before) that needs no revealer.
The long Down answers are also fun, with PILEITON (5D: Assign two projects, a long reading and several writing assignments, say), VERMONTER (32D: Bernie Sanders, for one), SLEEPSIN (39D: Has a lazy Sunday morning, say), and my favorite - HOTFOOTIT (9D: Run fast). I can imagine my mom saying that, which makes it seem kind of old-timey. Add to that SHARI Lewis, PEEWEE Herman, a Gran TORINO, and you've got a bit of an older vibe. Even NSYNC formed over twenty years ago.
But that's sounding a bit negative, and really, I don't want to. Sure, there were some oddities (like AFIRST (21A: What sending someone to Mars would be)), and I've never heard of DRU Hill, despite their having been formed prior to NSYNC, but, well, I just like the theme so much that I don't care, and will impose NOTAX for minor SLIPs.
My error, if anyone's interested, came at the cross of SIMILE and AIWA. I couldn't think of the erstwhile electronics giant immediately, and then forgot about it, and so when I came to 39A and saw SIM_LE, I dropped in a "p" without even looking at the clue. Rookie mistake, and one that took me more than a minute to find! Ah well... that's what I get.
In closing, I'd like to give a shout out to DUO Lingo, the free language learning app that allowed me to speak Dutch with the natives on our recent trip. It's like magic!
Congrats again to Ms. Slovut on this very nice debut.