I’ve come from a couple of PHEVs and then a full EV, and currently have a diesel T7 California which is also our main family car.
All things being equal I think I’d actually have gone for the eHybrid for our use. Day to day ours does lots of short family runs and the diesel can be pretty thirsty doing that, I’m seeing around 25mpg. On a proper journey though it’s a different story and 45 to 50mpg is quite achievable with a decent mix of roads and driving.
I do think there’s something to be said for the characteristics of the diesel in a vehicle this heavy though. The low down torque suits the Cali really well and it feels very relaxed pulling away, climbing hills and cruising fully loaded. That would probably be the main thing I’d want to compare when test driving the hybrid rather than worrying too much about the headline size of the 1.5 petrol engine. The electric motor should provide plenty of low speed torque and the battery doesn’t simply become completely dead once the EV range has gone, but I’d still be interested in how it feels on a long, heavily loaded motorway or mountain run.
The 4WD of the eHybrid would appeal to me too. My bigger concern in your situation would actually be payload. With passengers, a drive away awning, heavy paddleboards and all the normal camping gear, I’d work the numbers out carefully before ordering because it doesn’t leave a huge amount to play with.
I’m also not sure of the exact price difference, but I have around £6k in my head between the diesel and eHybrid. If it is anything like that, £6k buys an awful lot of diesel, so I wouldn’t choose the hybrid purely on the assumption it will save money.
For predominantly short daily trips with home charging, plus wanting 4WD, I can completely understand why the eHybrid looks like the obvious choice. If the payload worked, I’d probably lean that way too. If I was regularly doing long European trips, towing or carrying it heavily loaded, the diesel’s torque, range and efficiency on a run would still make a very strong case for itself.