Thanks all for the replies.

Regarding flying to SJC, this is simply because there are no Club World or First class reward seats available to SFO or OAK when we wish to travel (early August).

With respect to luggage, we'd just have one normal checked bag per person (similar to this one) plus a shoulder bag. There are no mobility issues anywhere. I just wasn't sure about Caltrain given the pictures don't make it look very easy for luggage storage.

I'll rule out Supershuttle, so it seems that it's essentially Uber or Caltrain.

The drastic option is to change our flight to the ~1pm arrival at LAX and then connect to SFO on AA, but this seems way OTT and much more stress.