Just wanted to update you guys with the progress, I finally resolved the issue and the car is running back to normal, no water pump leaks, no rough idling from all the coolant crust on the belt and pulleys and heater comes on hot only after 4 mins and at 24c.
I changed the thermostat along which resolved the issue, pretty easy job, got it done within 45mins.
Thanks for all your help and advice and hopefully this will be of benefit to someone else.
Many thanks