Tangentially, if you have some old external USB CD/DVD box collecting dust, especially those with their internal power supply but all will fit, don't throw them away as they are about the perfect case for fitting a SBC inside with the CD drive removed and swapped with a multi card reader+USB ports panel. Bringing out HDMI from the rear in a clean way can be achieved by using "HDMI panel socket"s that can be purchased online for cheap.