Shame to hear your not loving your T6 and hope you can come to a resolution that suits your needs, some great suggestions above!
I think the size is often more perspective than fact. As an example at my work the car park security guard used to moan for me for bringing in such a 'large vehicle' when I pointed out (we used to have a good rapport so used to giving each other some stick) that is was pretty much the same size as the Audi A4 that was parked next to it he agreed. looking up the sizes online its almost the same size assuming a SWB T6 (4.904m x 2.297m) vs A4 Saloon (4.72m x 2.022m) but the van just looks so much bigger as its taller and more box shape.
If you have a LWB then it is obviously slightly larger with the extra 400mm length
The driving position is much higher up so also gives the feeling of a much bigger vehicle, I find this a big bonus as it gives much better visibility on the road, especially on motorway when you can see over other cars.
As others have said A pillar handles, lowering and/ or step bars make it much easier to assist getting in and out.
My wife has a Tiguan which you don't think of as a 'big car' however I find manoeuvring the van much easier as the wheels are nearer the front of the vehicle so it turns much better.
The other thing to consider, if you don't already is a reversing camera it makes life so much easier!
