Yes. You are right. Because not all of us like and use the same coins, and not all of us have the privilege to buy coins that utrust may require. So i think having a wider variety of coins useable would be a great feature for utrust if it so gaooened that they implement this idea in their project. That will really be a great way to pull in a lot of people to use their services.
Which problems? I think more currensies will be better. Top 50 for example
Too many maybe? to list 50 coins you need to open and manage 50 addresses as well, and you think that people will trade with every top 50 coins? In my opinion just a waste if time and resources (and in top 50, even in top 10, there are coins/tokens not meant for payments)
I believe there is already a team doing a study behind the scene researching which altcoins can be used for the purposes of utrust's functions. Otherwise, we cant really move forward with this