My strength is a combination of communications and customer experience. What wows my clients is when I spend some time thinking of THEIR own customer experience and journey for their clients. Often clients come to me with a general idea of what they want, but they haven't thought out in detail what the process may be, and by bringing these things up to them, it 'wows' them by connecting with them, and letting them know what I really understand the project. This actually ends up helping me save some time in the end, to plan ahead, and not having to go back to update/fix things.
For example, in setting up an online store, there was a product that required advance ordering and I was just tasked to add it on as an item like all the others, but when I set it up, I actually attached a form to it asking their customer to confirm a delivery/pick up date as it requires a 2-day advance order. This wasn't something they thought about until later. They were very pleased that I had implemented this for them (even though it was something so little), as they felt that I was looking out for them and really know what I'm doing.