1. You can get in a state where you cannot adjust difficulty. I had upped it for an early campaign story mission, then all I had are "side" type missions no difficulty adjustment on all. I was getting OWNED and could not bump the challenge down. Why have difficulty just on some missions and not just add a difficulty toggle in options?
2. If you change the controller layout, some of the functions get remapped to touchpad. However, touchpad retains its "End Mission" functionality. I chose "Alternate" controller layout as the default felt alien to me,  and I also like to clear maps after the mission is complete. The problem is the touchpad is mapped to both pull up the map and end mission, and if you press it the game ends your mission.
3. Sometimes when the game comes back from suspend mode, it cannot connect. It just shows "connecting" ... forever.

Not really a bug, but framerate drops are surprisingly high. I play on both a PS4 and a PS4 Pro, and the problem exists on both. I have not tried multiplayer, but would guess the engine struggles even moreso with multiple players spamming abilities.