HEADS OF STATE
As the revealer explains, today's theme lays synonyms for "mind" over different states of matter. Thus, "brain" over "solid," "smarts" over "liquid," "wit" over "gas," and "noodle" over "plasma." Not a bad set. And the words themselves are hidden in longer phrases. I suppose the best one is POOLNOODLE since the meaning of noodle in this one is not at all related to the brain. Every other answer pretty much uses the key word in an unhidden way. Not that that bothers me terribly.
There are a ton of mid-length answers in this one that I like - OLEANDER (Poisonous shrub) always makes me hear Steely Dan's "My Old School" in my head ("Oleanders growing outside her door / Soon they're gonna be in bloom up in Annandale."), and likewise, since I've got music on the brain quite often, INFECTS (Passes along to, in a way) brings to mind The The's "Infected." IGNORATI (The uninformed masses, colloquially) is a fun one, and TUKTUK (Thai taxi with a repetitive name) makes me think of my brother, who loves to ride in those when he visits Thailand.
I didn't watch "Wolf Hall," but I probably should, because I hear CROMWELL mentioned a lot when I watch shows on BritBox, and I know almost nothing about that whole time in England. Frannie and I were just saying that we might try to make this coming winter into an extended "reading period," so maybe I'll break out some history books.
I didn't love what I consider alternate spelling in HOWDEDO ("Afternoon, pardner!"), and little things like ERY, EAN, and AQI are never really great to run into, but overall, I thought this was a fine Sunday.