Hi Oli, yes downsizing to your weight is a good guide, the new Sky Style 5'1" or the 2022/23 Sky Wing 5'2" are both 85L, both good, the Sky Style being the newer shape in the more exclusive technology. Def worth dropping down a size from 5'4, way more agile, esp in the waves/jumping.
Re the Aero vs Carves - if you want to keep your 1500, I would really recommend to go to the Aero Free 1000 as best allrounder, as you can still use that in quite strong winds, vs the 1150 Carve which may become too powerful in stronger winds?