Your van as an entity, is a very saleable item with or without an interior. Externally it's in great condition and styled tastefully to a high standard. Just carpet lined inside with insulation and electrics (installed by a competent electrician (YOU)) makes it a great base for a conversion to a day van, an MTB van or a full on camper. You can sell your interior and get a different interior for similar money. You may decide in a year or so it's time to get a bigger van. You can sell the van and interior separately or combined. You won't lose much, if anything. So get the interior you want. Don't over think it. Someone on here will give you good money for your current interior layout as has already been shown above.
I can relate on the cramped feeling of your current layout. If I could be bothered I'd put my interior up for sale - kitchen unit and cupboard, upholstered rib bed and matching front seats with folding bracket and sliding swivel and get twin captain seats and a U shaped layout. Having had belted rear seats for nearly a year now I have only carried 2 passengers in the back once.... so having belted rear seats isn't a necessity for me I don't think. If you're gonna have kids it would change things but in that scenario you'd be likely best with a Kombi set up with isofix rear seats and a full width ovano bed system anyway.
I can relate on the cramped feeling of your current layout. If I could be bothered I'd put my interior up for sale - kitchen unit and cupboard, upholstered rib bed and matching front seats with folding bracket and sliding swivel and get twin captain seats and a U shaped layout. Having had belted rear seats for nearly a year now I have only carried 2 passengers in the back once.... so having belted rear seats isn't a necessity for me I don't think. If you're gonna have kids it would change things but in that scenario you'd be likely best with a Kombi set up with isofix rear seats and a full width ovano bed system anyway.