Here are the quick reasons why I think it's good overall (never said it's wonderful)"
1. Prior to ACA, we had an informal "system" in which people paying full price paid for care for the poor/uninsured. To reduce this, consumers bought "insurance" policies that negotiated the rates down, so they were paying for less of uninsured. Forcing people to purchase insurance or having funds available, solves this problem. Refusing people care until some individual voluntarily pays would be a fairer solution, but I don't see that as being on the table. So given the choice between what we had making everyone buy insurance, I support the latter.
2. The model of insuring against unexpected medical costs as we insurance against fire or car accidents is breaking down b/c we can predict many illnesses long before they occur.
3. It eliminates the labor mobility problem of tying insurance with a job. That idea was horrible from the outset. People got sick and felt pressured to stay at a job to maintain the same insurance, preventing them from moving with the changing labor market.

The main bad thing for me is my family is reasonably healthy. We paid $400/mo for a policy with a $10k deductible. They measured our weight, blood, and asked us a million questions, including long questions about the time I threw out my back shoveling snow, so they know our risk profile is low. The premium will go up to $800 b/c our insurer said they expect an influx of people signing up who previously couldn't get an inexpensive policy. The premiums may go down after that. They say they're freaked b/c they don't know how to measure this risk and the rules keep changing. So we signed up for a non-compliant plan. We'll have to go on a compliant plan as of Dec 31 of this year. I did the non-complaint plan b/c I felt like it was like finding $5k that I'm legally entitled to lying on the ground. We picked it up.