Wheel wise if you look around you will likely find some carbon aero wheels for time trial bikes in the 650c size but these aren't necessarily lighter than what you have already.
Weight wise I can't see anything specific or cost effective to address.
My two bobs worth is that he/she just needs to start riding and training and as they develop and get used to the bike then issues may present themselves to be addressed. I can't see any point in upgrading first. My two bobs worth is that factors relating to fit are more important to address first than weight.