How can I upgrade my Worcester 350 heater control?

We have a Worcester 350 combi-boiler with a UT2 single-channel time switch to control the central heating. Temperature control is via the radiator thermostat valves. This is totally outdated and does not give us the required control over heater on/off times/days or decent temperature control around the house (sorry, bungalow). We would like to update the system, preferably without renewing the boiler, so we can control the heat across seven days and better control over the temperature of the house. Is it possible to install a more modern timer/temp control for this system?