I think you're right about your concern on vacation time, but that might be something you can negotiate. Also make sure health insurance is offered through your job. You pay for it, and it is expensive (a family plan might be $800/month), but it will protect you very well inside the United States. It won't protect you in other countries.

As far as salary in the US, you need to pay close attention to cost of living. Cost of living in a city like San Francisco, New York, or Boston will be very high. So do your research before you jump to the conclusion that the pay is better.

Finally, as far as liking actually living in the US, you also need to know that the different states are very different from each other. Living in Florida isn't the same as living in New York or Wyoming or Washington or California or Texas. I'm sure you might really like some cities and states, and you might really dislike others. Do you value diversity? Do you like big cities, smaller cities, or towns? Do you like more libertarian states, or states with more programs to benefit the poor? Do you want to live in a preplanned suburb, or somewhere older with a lot of local history? Definitely take a trip to possible relocation sites before you make a decision to move there. Destinations that some people rave about online might not be your cup of tea at all. People seem to love Colorado and California, and I was impressed with neither. However, I did like parts of Texas, even though people seem to indicate it's just overly conservative fat people there (I found it to be diverse and friendly). I also love the Midwest and big cities like Chicago where the food is second to none, and people are always out on the streets by the thousands, with street performers on all the major streets and parks. I'm absolutely certain there would be a few places you'd love in the US because different parts of the country offer very different experiences, but the trick is finding places that fit you & your family.