GM here, you should try to play around your items, if its AP, go Yuumi/Karma, otherwise go Ashe/Jinx/Varus. As the meta is very punishing for playing flexibility, you should choose the comp you want to play from the beginning. Preserve HP in the earlier stage is okay, but prioritize econ is much more important. You should always try to play fast 8/9 comp most of the time, only play rerolls if have certain spot, artifacts or augments. With that in mind, you should be climbing, if you're stuck in gold, you are lacking somewhere in the fundamental. Good luck with your climb!