Research into number of endpoints supported by USB hub controllers?

[drive by questioner]

Hello,

I'm running into issues running out of endpoints on the xHCI USB hub controllers on my cards.
I figured I'll just buy a new PCIe expansion card, but the marketing materials for these cards aren't helpful at determining how many endpoints each can support.

I then thought that I'll find the USB Hub controller part that supports the most devices & endpoints, and then look for expansion cards built with that part.
Even that is tough.  I've got the data sheets for two parts but neither is clear about their available memory, nor the design limit on number of devices.

Has anyone already gone to the effort of tabulating these parameters for a range of USB hub controller parts, and if so, would you be willing to share the winner?