That right there should be your answer to stay where you're at.
I've once lived in the summer in NY (lived with a college buddy) and WI (Madeline Island with a relative) although never spent any time in Milwaukee WI...
Cost of living and quality of life is a big issue for me. I'm not a big fan of Milwaukee but NYC I could never reside in reference to the city itself.
The issue is that you're asking the opinions of anonymous people that know nothing about your lifestyle/costs in Milwaukee in comparison to your lifestyle/costs in New York City (assuming you're not talking about some suburb in the state of New York). Also, you mention nothing about your family/relationships.
Without the info about family/relationships, Milwaukee has the edge and I think a trial run in NYC for a summer would be enough for you to make a better decision. Thus, a full year not needed. Yet, make sure you make arrangements in Milwaukee just in case you decide to return. For example, if you own your house/condo...sublease it for 1 year or rent it for one year.
If you're renting, you can make arrangements with your landlord to only sublet it on a one year term.
What's your cost of living in Milwaukee per year ?
What will be your cost of living in New York City per year ?
wrbtrader
30 and single. I think NYC would be more fun, but yes rent will be a lot higher. I pay $1400/month for a 1 bedroom here and it's nice but I actually don't need much right now and I don't make the full use of it. In NYC the same type of place will likely be 2.5-3X the cost. But I can go for a place that's lower quality than my current place but $2.5-3k a month in Manhattan. Or maybe try some other borough if it's decent. I would not be making a commitment to NY long term initially and I really don't want too nice of a place starting out there if I move.