To datawarehouse or not to data warehouse?
The main purpose of a datawarehouse is the ability to aggregate different types of data, and columns in a rapid way ( near realtime ) . Storage capability isn't the problem Datawarehousing is trying to solve. I can't really answer your question since i'm not quite aware of the volume of analytics you want to perform, but if it's for training a model over and over ( Online Learning ) , just set up a whole pipeline to apply the transformations you want ( the ETL part ) , model, train, and run your predictive method as many times as you want.