I had an ext cab Tacoma a few years back and hated that I had to open the driver or passenger door to then open one of the mini doors and then I had to have both open to get groceries into the back... it's just too awkward to me... easier to have a full door open.
IMO one of the biggest oversights in so many pickups is where to put small things like groceries.
That's why I love the Rambox cargo management system along with a tonneau cover. Ramboxes offer two drainable cooler type compartments on each side of the bed, and then in the bed itself you have a movable divider, which can also be extended out over the tailgate to increase bed length. I typically have this divider almost all the way up toward the tailgate, so that grocery trips and what not you just drop the damped tailgate, throw stuff into the back or the ramboxes, and it won't slide around since the area is small. No need to put it in the groceries in the back where it will just end up sliding around too and intrudes on passenger space if you've got 3+ people with you.
Santa Cruz we know will already have a very cool tonneau cover and its own little Ridgeline style trunk in the bed which is great, and even by itself it can act as its own convenient divider IMO just by leaving the tonneau cover forward, raise the "trunk" and leave it open, and voila you have a built in divider and it seems damped so hopefully it can just rest on the tonneau and not clack up and down as you're driving.
I still would want what I believe they generally call "bed extenders" somehow integrated into this area, or I'd remove the underseat storage and keep a bed extender similar to the one below under the seats (this particular one made for several different model pickups also doubles as a ramp when you fold it out fully):