Not sure if it is appropriate to post Crowdsupply campaign details here, but maybe someone might like this.
We designed a APA102C based 8x8 matrix panel system which can be used to quickly build up large matrices with no (or minimal) soldering. The panels themselves have 3mm mounting holes which also act as electrical connections for +5V, GND, Clock and Data. Using the Bus board accessory, the matrix can be made arbitrarily larger. The bus board also has provision for mounting an Adafruit Feather M0, or an external controller can be used. Multiple bus boards can be stacked to make larger displays.
The project is designed in KiCad and is Open Hardware.
Github repository is here :
https://github.com/wyolum/ultim8x8and Project details on our Hackaday IO page at :
https://hackaday.io/project/21430-ultim8x8PS: We're also doing a begathon on Crowd Supply so please help spread the word :
https://www.crowdsupply.com/maniacal-labs-wyolum/ultim8x8