Thank you for everyone's responses. A bit of background that informs my inquiry, if you would all indulge me:
1. First Wheelset Upgrade, from (stock) Mavic Aksium to Mavic Ksyrium Elite. Both alloy wheelsets have similar depth and profile, so main difference is a 230 g (~ 1/2 lbs.) weight loss, which was immediately noticeable in acceleration and handling (although I may not have the right adjective to describe the latter). To the extent I was any faster, most likely due to improving fitness.
2. Second Wheelset Upgrade, from Mavic Ksyrium Elite to FFWD F4R FCC. Going to a 45 mm deep CF wheel, with ~ 2 mm increase in width (both internal and external), and a 25 g weight gain. Noticeable increase in comfort, probably due to width increase and corresponding tire pressure decrease, and maybe slightly easier to hold higher speeds on flats and descents, which may be placebo. (But this upgrade also involved a tire change from Continental Grand Prix to Vittoria Corsa G+, so lack of control may invalidate the comparison.)
In my limited experience, I got a more noticeable benefit from going lighter than going deeper, so that may have colored how I approach this upcoming wheel upgrade. As noted in my OP, I do recognize that fun is not necessarily -- and in fact, is unlikely to be -- actually faster. I also recognize that now many deeper wheels in my price range only weigh about 1,600 g, a weight which I am now used to and is hardly a burden (especially compared to the 1,850 g wheelset I started road cycling on), so I understand the rationale to go deeper for some "free" aerodynamic gains.
[Armchair Psychology] Maybe the dilemma is just masking a reluctance to be seen as the fat slow poke with the deep wheels?