p.b
Forum GOD!
Yes, I can't remember what one we had but the 1+ was the size of an office chair.Maxi-Cosi Pebble Plus. It’s already pretty sizeable but, when we have to move up to a rear-facing seat for age 1+, room will be even more limited.
I had a Ford C-Max where the centre rear seat could be removed and the two remaining outer seats slide backwards and slightly inboard. That increase legroom by about 100mm and it still wasn't enough to create a comfortable seating position for the front row passenger.
Working in automotive development I spend a fair amount of my time watching crash simulations with front wheel drive transmissions hitting the LHD brake booster pushing the pedals into the steering column and shoving the steering wheel into the drivers face... Hence I tend to be cautious and aware of the magnitude of deformation that can occur in crash simulations / real-world crashes. If you're of a similar mentality then you'll end up with the biggest, baddest kiddy seat as I did.
I'd suggest a 1st generation Ford S-Max: Loads and loads of 2nd row leg space (it's limousine like!); great to drive and doesn't look too much like a out of fashion MPV.

