This is the actual ESP32 board which I ordered
(there are several item options in that ad, I bought the fully fledged dev board).
I would guess that at 520 KB SRAM and 16 MB flash, the ESP32 will be equipped to deal with anything I will throw at it.
As I said, the clincher for me will be if I will be able to load animated GIFs from PROGMEM. The ESP32 will very probably be eons quicker in displaying images from SDcard than my current 1284, but I still think that in a car environment, the SD slot could become a weakness over time. And changing the SD card would mean removing part of the center console to get to the back of the gauge to remove it. I'd rather have my graphics right where they are needed, i.e. in on-board flash memory.
Once all my graphics are in place and all the data from around the car is displayed correctly, I will make myself familiar with Android app programming, as the ESP32 has Bluetooth on-board, and programming an app where I can track and store my trip computer data over time was an idea for the project which I've had since its beginning.
I was reluctant to actually go through with it before I knew about the ESP32, because it would have meant adding another breakout to my circuit and thus increasing hardware complexity. But with Bluetooth on-board now, I see no reason why not.