"I obviously didn't have the command but was still able to offer input towards the flight taking in to account the rules"
Scoobster:
Your first post mentions a responsibility for Nav and RT.
I feel quite uncomfortable with this informal split of duties on a flight in fairly marginal conditions involving negotiating holes in cloud layers, etc.
Two basic PPLs together can feed off mutual bravado, which can quickly make you illegal (at best). Nice to have a glass cockpit, and electronic navaids, but stay within the provisions of your licence and capabilities.
I'm glad it worked out for you this time. UK weather is not as predictable as we would like to pretend.
But then I'm an old dinosaur...