Backyard ideas

Not sure if I've mentioned it before, but my man is having a detached garage at the back of the house. It's like a mini house and made out of steel frame, brick veneer and terracotta roof tiles just like the main house.

He is having a concrete path all around the detached garage (just like around the house) and wants a driveway leading from the (house) garage to the detached garage. Now the question is, should I let him concrete the whole area other than the grass labelled part or should I get him to only do a driveway path and then have grass in the highlighted green area? What do you think? I think either way there would be way too much concrete for my liking :(

The yard labelled grassed area is 13m long and 6m wide.