Late to this post, but also recently upgraded by 2019 Spark RC. I went with Elite Carbon Wheels (~1400g) with DT Swiss 240 Hubs. However, having issues with chain skip and shifting since converting over–working on mysterious issue now. Also, went with Carbon-Ti Axles which has improved the feel of the roll and has added a tiny bit of stiffness to the wheels. Looking also at the fall-line dropper to shave a few grams.