I don't know which model Volvo you have, but weight will obviously not be an issue. You will NOT realise the van is there.
As regards upgrading to a Triton, then consider these figures. I have swapped from diesel to petrol. My 1.5L manual petrol Audi A3 has 250N/m torque and 150 bhp. It pulls my 1200kg Triton better than the diesel Yeti did, to my surprise. It will hold cruise control in 6th up some fairly steep hills, is twice as quick to 60 with the van on the back and returned 33mpg over nearly 2500 miles through France this year, car and van fully loaded.
If you input the relevant details into https://towcar.info/GB/ then you will get some specific details.
Colin