You're talking out of your arse. There can be no positives to multiculturalism.
People point at the fact that we eat a lot of curries, or that there are a lot of Asian doctors, as justification. So what? They've given us new ways of cooking, not solved world hunger, and are filling jobs that could and would be filled if they weren't there. I've come across more incompetent foreign doctors than I have decent ones
They've also - and by 'they' I mean black and Muslim populations - been the cause of terrorist attacks, hate crimes, and disgusting, racially-motivated (or at least aggravated) sexual assaults. You pointing out that there are a lot of white *****philes is not evidence of anything. It is a red herring. It is ignoring that fact that non-whites are far more likely to commit certain crimes by saying "but look at how bad we are"
It really isn't a red herring to point that out, particularly since you're doing the same thing.
If anything, those crimes you mentioned (perhaps excluding terrorism) are pretty generalised across ethnic demographics. The areas of criminality which are most disproportionately committed by blacks and Asians are robbery, fraud and drug offences. You are correct that blacks and Asians do commit (or at least get prosecuted for) more crimes than whites in terms of of crime : population ratios, but then if you manipulated those statistics to take into account all the people living in deprived council estates across the country, and exclude those from middle class backgrounds, you'd find that crime rates roughly equalise themselves in conformity with demographics.