Yes the drone war is setting a dangerous precedent as far as fighting strategies go because everyone always looks to top the one before. This is not as bad as it seems though because the precedent could be a lot worse like nuclear war, instead of just drone wars as of now.
This is the question we have to ask when we are talking about setting a precedent. If we come up with all this neat justification for using drones to kill enemies and civilians, then those arguments will live on. This means that other countries might be able to use our same arguments when it comes to drone warfare or when it comes to using drones in our own airspace against us.
Every action, especially on the larger scale, sets a precedent whether it wants to or not. We won't know fully the implications of drone warfare until the future has arrived, but I believe that yes, it does set a dangerous precedent. Unmanned aircrafts dropped bombs on civilian sectors to take out "bad guys" based upon varying degrees of reliable intelligence data. I think that's a dangerous precedent and could lead to some really awful things in the future.
We are losing less lives of our soldiers, but at the same time I feel like we are creating more enemies. With civilians being killed, they are starting to resent us more and more. With resentment comes hate, and with hate comes more killing. It is a vicious endless cycle that all started because of greed over oil.