I just finished updating garageband to version 10.0.2. It has changed a bit.
Indeed, GarageBand has changed significantly. 🙂
I hope, you did not delete the older version, because some features of GarageBand '11 are no longer supported in GarageBand 10.0. You may want to use both versions. You will find GarageBand's old instruments in the "Legacy" section of the library.
And yes, GarageBand 10.0 has drum kits, that can play your own drum tracks. I don't remember, if the drum kits came with the basic version. Have you upgraded by installing the in-app purchase? Since you previously owned GarageBand, you should be able to download it using the command "GarageBand > Restore Purchase". see this link: Expanding GarageBand for Mac (v10.0) content with an in-app purchase