Hi,
I would suggest Scenario 2, having 1 multiprovider for all InfoProviders and play with queries as Anshu Lilhori says using InfoProvider restrictions.
Reasons:
1. You don't have to juggle around different MultiProviders when no of queries grows.
2. There will be many cases where you want to report data from different InfoProviders in same report. There will be problems when you many MultiProviders.
Note: Think of using MultiProvider Hint Table (RRKMULTIPROVHINT) to have better performance when you are executing query.
Hope it helps!
Thanks,
Umashankar