Hi Michelle,
IMHO, if you really want to be Project Manager as career, PMP is possibly the best choice. Try google for Top 10 Project Management certification, or Top 10 best paid IT certification, you will always see PMP on the list.
However, As for HANA, you have to understand that HANA is a In-memory High Performance Database. HANA is towards Data modelling, leverage on View/Table Modeling to massage the data for reporting, analysis or for other consumption. (Kinda similar to what SAP BW does, but with new technology).
S/4 HANA is the new version of ECC that mount on top of HANA, using HANA technology to boost the ERP system performance. S/4 HANA is still new, but it will grow and evolve and eventually replace ECC.
To be honest, I wouldn't say HANA is actually a SAP Module, but using an Application on top of HANA that will brings best values.
