1-2 was waaaay harder for me.
With my first it was so much easier to do the things i always did, he just tagged along. Of course it didn't hurt that he was a social butterfly and an all around calm, easygoing guy!
With dd, yikes. I always said if i had had her first, she would be an only! What an unhappy baby. She hated being little. As soon as she was mobile her personality did a 180.
When she was an infant, ds was 3 and still in diapers. It was hard balancing my need for sleeping and eating, with their needs for sleeping and eating..Dd wouldn't sleep and neither would ds. At 3 ds was fairly independent, and could do a lot on his own, but i always felt i was neglecting him somehow.
As far as logistics, i still dread taking them out together some places (they are 3 and 6) Its just harder getting two kids ready to go, buckling and unbucklng two kids, making sure two kids don't go running off etc...