Check Reserve Ammo by Looking at Magazine Pouches
Posting this again because my last one was removed for some reason. It has been said that in the future, limited ammo will be implemented, so I have a very clean and immersive way you guys could do this. Instead of just holding down a key, you could look down towards your mag pouches, and after (for example) 1 second, your magazine capacities will show up. The reason for the one second delay is to prevent accidentally triggering this if you just want to look at the floor or pick up a gun. This would require all of the operators to have mag pouches, so it would be a lot of work, but it would go well with the upcoming characters rework that Luca has hinted at. This is also just way better than a simple key so this would be a great addition.