Shower tub combo!
If it's the master bath I would want a separate tub and shower stall. But if your talking about the main bathroom or a kid's bathroom I would want the combo and the closet.
Now to convince the bubbs! And figure out some very tricky plumbing :) We don't have a master bath - just one for the whole house - and ONLY ONE closet outside the bedrooms as well...
It depends on how much storage you already have. Since I live in a smallish (832 sq ft) 2/1, I'd definitely go for the option with the closet. If you configure that closet carefully, you could make it your central laundry drop-off location (handy for bathing the child!) plus linen closet.
Separate shower/tub FOR SURE! I'd just try to get creative with storage space to make up for it.