The Blues will be in command when the second leg kicks off at Stamford Bridge next week after goals from Tariq Uwakwe, Callum Hudson-Odoi and Charlie Brown at St Andrew's made it 12 wins in a row for Morris's side in all competitions.
"I thought we were really good off the ball," Morris told chelseafc.com. "We worked hard and pressed hard so the majority of the game was played in their final third. With that much of the ball and territory, we should have scored a few more goals and we could have been better with our final pass, our decision-making or the execution of our finishing.
"The tie could have been dead and buried but I was pleased with the intensity we showed off the ball because that was something we wanted to see from the lads, for them to show they're not just a quality football team but we're really hard to play against as well. We got another clean sheet and there were some outstanding individual performances from Tariq Lamptey and George McEachran in particular."
Morris also commented on the passing of Ray Wilkins.
He added: "I was absolutely gutted to hear about his cardiac arrest last week but I was really hoping he'd pull through so to hear the news before the game was just devastating.
"Ray was a class act on the pitch and even more so off it and he was so good for me as a young player. His support never wavered even when others might at certain stages of my career and life. He was always on the end of the phone offering positive advice and I spoke with him a lot, even as recently as a few weeks back when he messaged congratulations after we beat Tottenham in the Youth Cup.
"He had a really keen eye on our young boys, partly because he was himself a home-grown Chelsea player, and there was nobody more vocal than him in pushing for our lads to get opportunities. He was a top-quality guy - it's such a sad loss for his family and for the whole world of football."