While the OmniPro has been a reliable HA system for many years, it's obvious that it's best years are behind it. Leviton has moved on with other products that don't really replace it.
With regard to the multipurpose sensor, it's OEM'd from CentraLite (p/n 3321-S). There's no technical reason Leviton couldn't support the vibration, temperature, and contact closure features. However I doubt anyone there is actively working on any new integration projects for the OmniPro.
After spending a little time with the SmartThings hub and multipurpose sensor, I can find quite a few applications where I would like to use them. The hub also works great with Amazon Echo Dot, another thing not supported on the OmniPro. I don't like the cloud aspect of the system, but I can except it for these functions. (I would never trust it for security or door locks.) That said, it would be great to find a way to link the SmartThings hub and OmniPro to get the best of both worlds.