Meant to reply to this yesterday. I can assure people that a riot shield class doea not give you more health. This isn't based on any testing but just my experiences. As for the hitmarkers, i think that sometimes hitmarkers come up when you are shooting into the shield. Again not proven but i'm sure people have said this to me.
As for the danger close c4, that isn't a riot shielder issue, it's more people using nooby class. Equipment has been made easier for us to use but that's a deserved buff in my book. Cant remembet but are trophy systems in Ghosts?