TriSept has just the answers you are looking for...
TriSept “Rideshare” capabilities allow you to be manifested on a larger spacecraft’s mission.
3U CubeSat Class (P-Pod, X-Pod)
Experiments / R&D payloads
This shares the costs of launch services proportionally among all spacecraft.
TriSept takes advantage of the mass and fairing volume margin to add smaller spacecraft allowing
more efficient access to space for all while reducing individual launch costs without an increase in risk to the mission.
TriSept's existing corporate relationships make us uniquely qualified to offer configurable adaptors establishing a standard mechanical and electrical interface with the secondary payloads attached to the adaptor, not the primary spacecraft.
Additionally, TriSept will perform all secondary payload integration and interface testing, and can offer Primary-to-Booster integration options
This is not just a conceptual idea
We have done it and would be happy to tell you about our corporate capabilities, experience and previous missions.