To easily reproduce the problem:
(1) create a new character, choose female
(2) select Clear so you've got the basic setup
(3) select Lower Body = Monstrous, and Feet = Cat Claws
- observation: your character is now 2/3 legs (and even more so, were your legs fully extended)
- this can be somewhat mitigated by lowering Legs scale to minimum, but it's still silly
(4) increase Physique slider to max, because we're a buff female monstrous character
(5) rotate character to side view, scream in horror at the body proportions
Seriously, this combination looks terrible. The male model handles this reasonably well, and the huge model handle this extremely well. But the leg proportions are just ridiculous on the female model -- you look like some sort of half-grasshopper monster. The leg juts out behind the character way too far, and the digitigrade foot is way too long. Lowering the Physique slider helps avoid the worst of it, but results in an emaciated look overall, which is terrible for other reasons.
Would this be fixable via a tweak to the wire model, or whatever governs how the leg proportions change with the Physique slider? Obviously the male and huge models handle their size changes well.
A fixed model might need to be a Monstrous 2 option, to avoid breaking existing characters...but I doubt that many people would prefer the existing model over a corrected one.