You can always buy anything you've forgotten
The only things that I would think essential are any items that are part of her sleep routine (the book you always read, her blanky, her ted, her sleepy CD - that kind of stuff). I forgot Yasin's musical teddy on a trip OS once - never again!! I bought another one but he knew it wasn't his ted.
If the pram is taking up alot of space and your budget allows it maybe you could get a lighter pram for travelling. I've got a little one (7.7 kg) that I hardly ever use except when we're going away.