I will join, but I totally agree with you on the above.
We must always be civil and acknowledge that some people just really don't like his music, and are allowed to voice their opinion.
Personal attacks on Mika do vary in seriousness, from snide comments (Manchester Evening News, anyone???) to what verges on incitement to violence on Facebook and our responses need to fit the crimes, so to speak!
So yes it's a good idea but it has to be measured.