Small TowCar for Freedom Discovery?

I've bought a 'Freedom Microlite Discovery LE' (750kgs) and need to change my car (have wanted to change for a while).  Want a small diesel car/MPV 2008-2010  - needs to be up to 9 weeks in France every year for the next few yrs and a good wee car doing solo the rest of year.

Fell in love with a Fiat Qubo 1.3 which the dealer insisted would pull my Freedom - further research and a call to Freedom in Stratford and the Caravan Club confirmed it wasn't.

So now looking at a Citroen C3 Picasso 1.6 or a Citroen Berlingo 1.6 (although no loyality to Citroen).  Towcar.info gives the C3 the edge over Berlingo - http://www.towcar.info/uitvoer.php

Any other recommendations for that kind of size of 5 seater MPV? Do I need a 1.6 or could I get by with a 1.4 or 1.5?

I'm on the West of Ireland so will be clocking up a lot of miles around France etc.

Big thanks for your responses in Laypersons terms :-)

E