Manage datasets (universe)

I have two datasets. one is only for certain users. i had to create for the board a report based on the two datasets. The problem is that i had to create all the steps, import sources etc because we canT merge two dataset. I can not use only this merging dataset because some user have excel extract from online where they have all the datasets and then can not access one of the two dataset. In business object we can manage easely all the dataset and decide after who has access on what. this is easier for big company. You imagine i have to recreate each time the full dataset.