That's a very sensible and achievable target time, after all for your first marathon your main aim should be to try and enjoy the experience, a half marathon pb shows the training is going well. I would like to get close to my pb of 3:21 but will be happy with anything under 3:30.
I'm in too, it will be my 11th marathon, had mixed results in the others, usual things like going off to quickly and blowing up, struggling through lack of training and sometimes doing better than expected when it all comes together on the day !
Not done Vienna before but have visited twice and love the city.
What sort of finish times is everyone hoping for ?