It is somewhat disingenuous not to include the various patches required to sustain the theory. Inflation and Dark Energy being the most obvious, but Dark Matter should be included, in that we don't really understand gravity either.

If space really did expand, wouldn't the speed of light have to increase proportionally, in order to remain Constant?

Instead, two metrics are being derived from the same light. One based on the speed and one based on the spectrum. If the speed were the numerator, it would be a "tired light' theory, but as an expanding space theory, the speed is still the explicit denominator. Consider all the ways this expansion is described and measured and they are all in relation to the speed of light. That it expands in relation to the light crossing it. Lightspeed remains the constant, relative to the universe expanding. Which would make speed the "ruler."

Given gravity does cause space to "collapse," yet this expansion only applies to the space between the gravitational vortices of galaxies and that this relationship is inversely proportional, "Omega =1," it would seem an overall equilibrium. Essentially some cosmic convection cycle. Basically that Hubble did discover Einstein's Cosmological Constant and it does exactly what Einstein proposed, balanced the effect of gravity.