Howdy Y'all! Over the past year I have been working on a display font inspired by the title lettering of a series of murder mystery novels from the 1920s. It is the second full font I have designed, and is tentatively called "Philo"; however if anyone has a better name, I'm all ears. The original novels provided the basis for most of the capital letters, but the lowercase, numbers and punctuation were extrapolated from there. This typeface will ultimately include 2 styles: a "title" style and "subtitle" style, but I would love your feedback and sage counsel on this initial title style before completing work on the second. Thank you!

Comments
The original lettering had that capital “O” with a major top overshoot and an even more exaggerated bottom overshoot, almost like a bit of a descender. I would be curious as to how well it would work if you dialed back that bottom overshoot, making it only as much as the top. Which is still substantial, just a bit less.
I would try a much smaller counter on the lowercase “e”; the current design tries to preserve the design theme of diagonal counters from the cap O, but at the expense of a broader theme of small counters. I would also make the counter of the ”a” ~ square by moving down that middle bit.
Lowercase v w are a bit too wide. Perfectly reasonable to consider giving them a wider angle than their cap counterparts, but I think it has gone too far.
The diamond tittles of i and j can be noticeably bigger. Especially if you lower the x-height...
Which is my big question. Why is the x-height so huge? Most of the contemporary work from the 1920s and 1930s that deviated from “normal” x-height, went in the opposite direction of small x-heights. To me, the big x-height makes it feel more like a 1970s mock-revival of a 1930s style, rather than something more genuinely of that period. If you want flavor in the x-height, I would try going small. Average is also fine, if you like. But extra-large x-height feels weird to me, in this context.
Ditto Ray on the period.
The Euro could do with more heft.
Favourite Philo Vance: Basil Rathbone in The Bishop Murder Case.
In a more conventional design, and at text sizes instead of for display, a smaller x-height might also need slightly wider (proportionally speaking, not absolute) glyphs—but not so much with this typeface. IMO, anyway.
That said, the smaller the x-height, the more difference makes sense between cap stroke thickness and lowercase stroke thickness. The usual difference is something like 4-10%, probably 6-8% is reasonable here, if you have a more conventional x-height.