If you count the abuse of the rights of millions of Iraqis then I'm sure the US is up there, but domestically of course the US isn't as bad as many other countries, but your (or rather our, the UK is no better) leaders actively support regimes, such as Saudi Arabia, with a much worse human rights records than Cuba.
Cubans are dying crossing to the states for the same reasons Africans are dying crossing the Mediterranean. I don't doubt that some are genuinely fleeing persecution, but most are simply seeking a better life, economic migration.
Would people see things differently if Cuba was a democracy and Mexico was Communist? Or maybe a useful military dictatorship? Easy to convince the sheeple that human rights abuses there aren't as important as ones in Communist (or lately, Arab) countries.
Human rights abuses are important everywhere. I'm not going to get dragged into another idiotic debate about us in Iraq, yes the war hasn't been managed properly, no we did not go in there for the purpose of murdering women and children.
Being a former military man I can assure that our training involved none of that. We did however learn amongst ourselves to kick some hippy ass

Seriously, if people would take the blinders off for a second, and realize just how many restrictions are put on us as far as rules of engagement, you'd be shocked.
As far as Cuba, I was born there. I have had family albeit not immediate (uncles ,cousins) executed and imprisoned, and no they weren't criminals. My father in law was imprisoned for a year and a half at the age of 14 for attempting to flee, he was by the way thrown in with common criminals.
Liberal elitist like you sit there and rationalize everything from your comfy homes, with your stomachs full, and throw out all the talking points which are only meant to do one thing, blame America. I was lucky enough to have this country welcome us, and by the way I did it legally.
I'm glad I did get out so I could respond to people like you, had I stayed in Cuba, I would of never had the chance since internet access is not allowed.