Uavs must be a 4 or 5 killstreak. They ruin all cod games. They give away positions and it makes people use the OP assisin perk types. If it's a higher K-Streak people would be able to use and practice other perks.
Sorry.. but how does it "ruin" CoD? Its a streak meant to help your teammates. You complain that it makes Ghost OP... but if there were no UAVs.. what would the difference be? Its currently a 3 kill streak, how is it better at 4 or 5? I understand your point, there is a lot of UAV spam in the games (I hardly think it ruins CoD, I think its meant to keep the match moving).
I don't have an issue with it being slightly higher. If they keep it low, it should be easy to spot and easy to take down. Perhaps they could also do the same with UAVs that they do with choppers. If you get chopper, there can't be more than one in the air. Maybe make it so that UAVs are the same way. Perhaps make a 10-20 reset time before the next UAV can be called in.
UAVs are an essential part of the game especially in Hardcore. Maybe the answer isn't changing the UAV, but removing the minimap entirely from Core as well as rankismet suggested on another thread. This would make UAVs valuable commodities and encourage more people to take them down.
Otherwise, stop chasing red dots. The UAV serves its purpose, as do counter UAVs and Counter UAV perks.
At this point, looking forward to seeing the MP reveal to get more answers.