Possibly lower end MV and add temp sensor with alerting. Use case would be server rooms to see who is accessing the rack and monitoring temperature in the room.
Next would be hardware similar to Chromecast that could stream the video wall, but would be totally controlled by Meraki. Possibly this device could have AI built in so you could query the API or dashboard, like hey gnomie what is the latency on the wan? or hey meraki what is the highest usage device in hq network?
Another one would be Low end MX or Z series device to support 25 users. Z series is often undersized for SMB office and MX is often oversized, Maybe call it MZ
USB key or super small physical device, replicates similar capabilities as the Z1, but at a much lower price point. AutoVPN is needed, reduces need for client VPN on endpoint, config is almost zero touch.