Its an interesting one, as coming from someone that never understood how to find challenges and camos in all of the older CoD games, this one has been the easiest to find by a mile. I think they could make some tiny tweaks to it, like seeing which ones are unlocked/locked but I think ALL the CoDs could have explained Challenges and Camos far easier. Its clearly an objective that drives people to play more so I've never understood why they don't have a separate tab at the top with all the key things you may want to focus on.
Outside of that, I only find the party system a bit of a pain....and even then, its no way near GTA's version of a party system. Its pretty easy to get crossplay people in too. @Dylanimo16 joined last night and it was extremely easy and the Whisper system worked well.