I'd be basing my decision primarily around which models fulfil my needs - be that in terms of portability, battery life, display quality, performance (CPU and GPU), ergonomics, etc. Right now, there is much less choice of AMD-based laptops, and they currently tend to be on the low end of the scale in terms of everything but performance. After years of integrating and tuning systems with only Intel CPUs, the laptop makers have yet to get the hang of making high-quality AMD-based laptops. I suspect this will change over time (Microsoft's aforementioned Surface Laptop 3 is a good sign in this regard).

If you're keen to support the underdog and can wait a few months, you can certainly wait for Renoir to be launched. I suspect AMD are itching to get a piece of that giant laptop revenue pie, so even if it ends up being Zen+ with Vega, AMD might have spent that time instead fine tuning idle power draw and thermals. Performance of their APUs is already decent, so such fine-tuning might be enough to get some high quality AMD-based thin & light laptops to market.

If you need a powerful (discrete) GPU and would prefer to go with AMD over NVIDIA for that, the upcoming Navi-based Radeon RX 5500M is one to watch, be it paired with an Intel or AMD CPU.

Disclosure: I skew towards AMD for both GPUs (in preference to nVidia) and CPUs (in preference to Intel) when it makes sense. I've got a Ryzen-based desktop system, but there are more Intel-CPU-based systems in my office, to a large extent because I do Mac-based development professionally - I think I bought my last AMD-based laptop in 2005.