I hope to move things from this list to the one below.

• ARM MCUs
• Ultra-low power MCUs as power source will be an important IoT criterion
• CPLDs
• FPGAs
• Reflow soldering
• Use up the retro components in my stash
• Use the nixies I have
• Make things with the discarded technology I scavenged
• ...
• A robot that will do all the housework, and amuse the cat. I mean that would be the greatest step towards world peace. 😁

Things I have done

• Restored past projects in my junk box
• Arduino
• ESP8266, ESP32
• 8042/8048 MCUs
• 8051 MCUs
• TM1637 two wire interface
• I2C
• SPI
• Various displays: LED, OLED, LCD, TFT screen
• Rotary encoders
• DS3231 RTC
• Kicad/eeschema, pcbnew, freeRouting
• Small Device C Compiler
• Ordering PCBs from a fab
• Designing PCBs in Kicad
• GALs
• eForth
• Had SMD boards fabricated
• Soldered SOP and TSSOP packages
• STM MCUs
• AVR MCUs
• Made a 6 segment digit display to close off a half-century old project
• PIC MCUs

Still no big project in mind, just building skills, nothing that I really need or fancy, so I guess I'm contented.