Enthusiastic and inspired by your successful navigation of that first anagram, you go searching the grid for others, but identifying an anagram indicator, it turns out, is not as easy as you might think. Thankfully, the setter is hovering over your shoulder and points out two more anagram clues, just to stop you having to think too much. This is supposed to be fun, after all. First up, the erstwhile setter points to 15 down...
Flourished to rivet HD tuner (7)
I'll admit it, it's an ugly clue, because the surface meaning if just a bit too much of a stretch. If I wanted to grammatically correct, it would probably be more like "Flourished to rivet a HD tuner" or something (still ugly, but better), so the odd sounding sentence structure is your first clue that something fishy is going on. Combine this with the fact that 'rivet HD' has 7 letters and 'tuner' has some vibes of static and change associated with it, and you can be pretty confident that here you have another 7 letter anagram that means 'flourished', and you can understand why I've let my prized grammatical correctness slip for a little while.
Also on our little list of anagram clues is 6 down:
Philosopher is all about tea hour (7)
Tea time, yes, tea break, even, but tea hour? No-one takes a whole hour to drink a cuppa. Again "all about" is looking an awful lot like an anagram indicator, so we're on the lookout with a philosopher who shares his letters with 'teahour'. This is not to say that anagrams are always able to be found by looking for gramatical weridness, but it certainly gives us a nudge in the right direction.
In this case, the philosopher in question is Mr. THOREAU, whose theories have THRIVED greatly since his death. Not being a philosopher myself, I can't say I've read any of Mr. Thoreau's work, but if the letters fit the letters fit, and I couldn't really resist chucking him in, philosophers are classy and erudite, after all.