I am that not satisfied with the Arduino's microcontroller's power (but of course satisfied with the I/O on the Arduino mega).
- at least 4 cores, and
- at least 4MiB of RAM and running at 50mhz (or more), and
- at least 40 I/O pins (that is not analog or PWM).
Which is the best microcontroller for this?
If possible, make sure uploading the program is simple and does not need the chip to be put in some specific programmer. Plus, make it as cheap as possible :).