It appears with dCore-buster64 that both Intel i915 and Nvidia chips need their kernel modules available for X to function. When graphics-4.19.10-tinycore64 is installed for intel, and nouveau-4.19.10-tinycore64 for Nvidia, X will start and work. There may be other chips that need the same.
PDP-8 - as your setups are working, I hesitate to add the graphics kernel module to dCorePlus-buster64 as it is the only release of dCorePlus that needs them with any of my hardware, it seems like a fluke with packages in dCore buster64.
But dCorePlus should just work, and the graphics modules in this case would be a 3 MB addition of size, I am pondering adding them as this is also the newest Debian based dCore offering.
In any case, if anyone has a problem, they should come here and this post is a notice that some graphics chips may not boot to X without their related kernel modules present for dCorePlus-buster64. All other dCorePlus has booted to X with me on both Nvidia and Intel chips. If you boot dCorePlus-buster64 and it falls back to the console, use the below commands.
sudo wifi.sh # then set up your wireless connection
# For Nvidia:
sce-import nouveau-4.19.10-tinycore64
sce-load nouveau-4.19.10-tinycore64
For any other video chipset:
sce-import graphics-4.19.10-tinycore64
sce-load graphics-4.19.10-tinycore64
Make sure of course that when you load graphics-4.19.10-tinycore64, nouveau-4.19.10-tinycore64, or any other graphics related extension that you do not do it in a running X session.