Not following your back seat comment and there is a roof rack available.I went to look at the Tesla model 3 last week. Looked like a really nice car, but it will for sure not fulfill my/the familys needs as the familys only car. (No good back seats, no way to extend cargo capacity - no hitch or roof mount). So unfortunately i am going to ditch my reservation.
On the other hand, there appears to be interesting cars in the VAG pipeline, and others too;
New Skoda Vision E concept review
https://www.autoexpress.co.uk/best-cars/103133/best-new-cars-for-2020-and-beyond/page/0/1
I drove myself and three family members up to the mountains for a week and didn’t even get close to maxing our storage.