After last night's discussion on Alloy, I wonder whether a problem with Alloy is that too many pins are connected to the ESP32 rather than the FPGA. Since all the feather pins are connected to the ESP32, any hardware connected via a breadboard will be connected to the ESP32, and the same for any hardware connected via feather wings.
With these products that are a fusion between a microcontroller and an fpga, I think the use cases where you want hardware connected to the fpga are much more common than where you want it connected to the microcontroller.
From my experience with the Ulx3s, the exception is the sd card reader, as the SD card is more often accessed from the ESP32. But on the Ulx3s the sd card pins are connected to both the fpga and ESP32 so you can access it from either.