Good design fulfills the needs of the end user. Great design fulfills the unknown needs of the end user.
As for your future endeavors, I highly recommend you partner with your marketing group. Do not make it adversarial, do no create silos. Their task is to find customer problems and have the customer evaluate your solutions to those problems.
Of course you can do all of this work, but that would be inefficient and it requires different skill sets. Marketing is about creating the relationship with the customer. As a rule of thumb, most creatives are introverts who spend a lot of time in their heads. Not the best attributes for creating relationships. And don’t forget the great length of time it takes to create those relationships. Cuts greatly into the problem-solving time.