Thanks everyone for your suggestions. My SIL wanted to sell me their verve but I regrettably said no before I realised it was going to be one of my only options. Damn! I also had really liked the idea of the toddler being at the front not underneath as DD is won't even sit in the shopping trolley without being able to see where she is going (I often have to push it backwards so she's forward facing for at least part of the trip).
Will take another look at it in store though and the Valco and Strider Plus. They look a bit more like what I'm after.
Very grateful for all the help.