There's a new ESP chip out (ESP32). https://espressif.com/en/products/hardware/esp32/resources
It features 2 240 MHz 32 bit processors, 512KB of RAM, Bluetooth, and WiFi. It does consume quite a lot more power than the 328p processor though. I'd be willing to work with someone who has mechanical design experience to make a gamebuino clone out of one. I can't seem to find the chip without a dev board so it might be a while before a device can be designed and assembled.