Congrats, dude! My wife and I had our first little one in July and he's almost (almost!) sleeping through the night.
Congrats to you as well;) My son was allot harder than she is so far, and allot of that I think was we weren't used to being parents at that point so it was much tougher;) I don't envy your position, because I know how I felt back then sleep deprivation wise;)
I will say with the second one, honestly she's super easy compared to my son being the first. Hardest part is honestly Eli's emotional ride more so than the baby. It's caused him to act up and just be a pain in the ass which is completely out of the ordinary for him. Normally he listens well and is really well behaved for a 4 year old, but man he's been driving me nuts;) I love him to no end but he's getting better day by day coming back down to normal so it's just time and getting used to things. But overall things went well and the second kid is far easier;)
Luke