First Time Visitor - which ticket?

As a seasoned Disney visitor, I’m planning my first trip to USH (either with a small group of friends or solo) on either 12/13 or 12/14 and I’m debating between GA vs an express pass.

It feels like there’s far less to do than compared to park hopping at Disneyland and California adventure so I don’t want to assume GA will be sufficient to do everything at the park but I don’t see how an express pass would be necessary.

If solo I’d plan to single ride most things - if in a group how long should we expect waits to be for things like mummy, JP, or Mario on a Saturday during the holidays?

I appreciate any guidance and tips you may have in general. Thanks!