I am doing
I would say it sounds like your mind is made up!
Regarding being overweight with twins, I was about 30 pounds overweight to begin with and my boys turned out fine. Around 25 weeks my blood pressure went up, so I had to take Labetalol for the rest of the pregnancy. Then around 32-33 weeks it eventually stopped working (I developed mild preeclampsia), so I delivered at 35 and 5, but my boys were only in the nicu for 12 days, and that was simply as grower and feeders.
Weight gain wise, I gained about 26 pounds. My doctor recommended between 30-35 pounds, but being I was overweight this was perfectly acceptable.