Delay Reducer...
If you're going to be graduating with a BSc in ATM would you not aim a little higher than an entry level ops job? Plenty of companies out there have internships for new grads and they probably pay much better than an entry level ops bod...With an MSc in ATM most ops departments will frustrate you as you'll not have much opportunity to put what you've learned into action unless the ops manager/director allows you to do so and such side projects would have to fit in around your regular shift patterns.
Raytheon / Airbus and some of the larger airlines regularly hire new grads and offer rewarding careers.
Just something to consider.
As for the original question....
Ops controllers these days should have excellent commercial awareness and cost control knowledge. How many even know what the cost is to operate their aircraft for 1 hr? It plays a big part during disrupted operations and recovery planning. Some of them out there have plodded on for 2 decades and muddle through anything to do with the cost aspect of things, no excuse for that anymore.
Impeccable attention to detail is also essential. Never stop learning.