How much more would you need to make to be worth being a 1099?

I look at it this way, when you 1099 yourself you represent yourself as a mini business to your employer. You're responsible for the overhead and risk of that business. That additional cost and risk could easily could represent 2x what a standard salary rate would be for the same position.

Keep in mind contractors can't be expected to be employed consistently, so they have to bake in additional income to tie them over between jobs, or handle the possibility of being unexpectedly terminated. They're trading additional income for added risk and uncertainty.

I'd want double to cover the cost of getting my own health coverage, my own life insurance, and to deal with tax complications that come with being a 1099 and not a W-2 employee.

And I'd also want contractually guaranteed time and a half for overtime.

There is a benefit to 1099 income that you did not mention -- when my physician wife gets 1099 income she is able to contribute more to a SEP-IRA than when the same income comes with a W-2.

Insurance benefits are the major difference usually. also, does your employer expect extra hours for being salaried?

but you could be the first to be cut if your 1099.