When we had Mini we were just learning how to be parents. We did our best to make the right choices; sometimes we probably goofed but overall we did pretty good, I think. Be that as it may there are always choices you wish you could have a "do over" on. That is what second children are for. ;-)
We get the chance to things differently the second time around. For better or for worse.
Some of them are purely for survival and others because we figured out that they ended up being an issue as Mini got older:
Pacifier- I didn't push it with Mini because I pretty much was always able to pick her up and comfort her, with the twins there is just no way. I need Little, Little Man to be able to gain some comfort on his own while I deal with Mini or Big, Little Man and visa versa.
Breast feeding/Co-sleeping/2am feeding- We co-slept with Mini until she was 10+ months old and she was breastfed on demand. It was not possible to co-sleep with both boys and they both had latch issues so I pumped and bottle fed them before starting formula at 6 weeks. Once they were old enough we weaned them off the 2am feeding because the lack of sleep was becoming detrimental.
Pass the Baby- I'll admit it with Mini I had a hard time letting others hold her (& this included her Daddy!) With the twins I am quite willing to hand them off to whoever wants to hold them. :-)
I am sure there are more changes to come as we learn what has worked and what hasn't with Mini. Of course, there is no guarantee that it will help with the boys. ;-)