A bad glow plug will make starting hard but won't make BLUE smoke. Blue smoke is oil. What oil was put in at the most recent change - was that also Delo 400?
My guesses are turbo seals, valve seals, or the crankcase breather circuit for the blue smoke. Hard starting is probably glow plugs or valve adjust. But that "miss" is not good...! Hopefully the valve adjust will fix it. Otherwise it's time for Diesel Purge, or testing the injectors, or doing a compression test. My cars fire on all cylinders & smooth out within 5-10 seconds of starting, not 60-120 seconds. Yours should too!
