I am a hopeless packer, I tend to take three times what I need 'just in case' Maybe you could start by imagining a typical day and all that you would use for sure. Then you can add extra stuff as you think of it. What about breaking it down into routine times? eg. sleeping, eating, playing, bathing, etc. The weather here is difficult to judge right now but probably does tend more towards hot. I use a .5 grobag or my other even lighter one with just a singlet onesie, though it sometimes gets cool towards morning. I personally haven't used anything long sleeved for quite a while. If you had a light kind of cardigan for her, I would say that would do for the cooler times. It's so hard when it's someone else's baby to say what you would miss...