She is gorgeous! And welcome!!
For now, A time really is limited. Yes, it is usually just a diaper change. If you can hold off on the change until just before she goes to sleep, that is great. The key is to try and NOT let her fall asleep while feeding, as this becomes the 'signal' to fall asleep, and as she gets older, the concern is that she will rely on it to fall asleep and not know how to do it on her own. So you just want to break that up, even if it is a 2 minute diaper change.
If you can't wait to change her, just burp her and lay her on the floor and try and get some eye contact before she goes to sleep. In a few weeks, you'll notice that she has some time to spare before dozing off, but right now, she is still tired from her 'journey'.
A dreamfeed is a feed that you sneak in while the baby is literally sleeping, just before you go to bed. Like the cluster feed, it is to up the calories now, so she sleeps longer at night, and you do too! With the cluster feed, it is before the baby goes to sleep, but the dreamfeed is where you pick the baby out of bed and nurse (or some keep in the crib and give a bottle). Dreamfeeds aren't recommended for awhile yet, I *think*6-8 weeks old, but you may want to double check on that. Some don't need it, others are bothered by it, and some - like my ds - were fine taking it.
Hope that helps!