Power BI data sources/Architecture

[mcornfield]

We are rolling out Power BI at my company, and I have the unique opportunity to advise IT on how we should house/structure our data to work best with Power BI.

We have a lot of data, so we need to use either a live connection or a direct query.

We also need to be able to combine multiple sources like SharePoint lists etc.

We currently use a live connection to analysis services - tabular model - Which doesn't let me combine to other data sources.
Our other option is to SAP HANA, which I can only bring in one table and no others and cannot combine with other Data sources.

I am not too knowledgeable in Data warehouse/Data Architecture, so all suggestions are welcome, and the more detailed, the better. I don't believe we plan to get rid of the current data sources but maybe add another one?
Pros and cons of anything you suggest would be helpful; someone at my company mentioned snowflake not sure what this is.
Thank you!

[lbendlin]

"We have a lot of data, so we need to use either a live connection or a direct query."  Not really.  Power BI Premium can support data models far beyond 10GB size if you are willing to pay for a P3, P4 or P5 capacity

The new composite model allows you to switch from live connections to direct query, while at the same time allows you to create local clones of the data models, and to combine multiple data sources.

What is your company's position on using Dataverse?  The one thing Power BI is definitely missing is a data stewardship module, so you would need to look into Dataverse, Purview, or other (including open source) data modeling tools to keep your company's data subjects under control.