I don't think I've seen a latency spike on AWS in 10 years. Hetzner, it's often possible to observe latency and drops over 10 minutes (and the situation hasn't changed much in about 10 years)
The primary issue I have with them is latency access to their DE/FI data centers from the US, if their US DC offered dedicated servers I would be migrating to over to use them instead.
If you haven't experienced Google translating insistently German responses from one of their DC techs you probably haven't been using them for long enough ;)
As for networking, would encourage installing something like Smokeping
But I don't really access AWS support either, when something doesn't work I've just killed the VM and started a new one. It's less disposable with bare metal servers, I can physically restart the server from their control panel or if issues are not fixable, reset the server with a new Linux OS image, which granted would be a lot more time consuming.
I will add that whilst I'm not in the business of dictating which cloud services business customers would use, I'd agree that I would recommend AWS over Hetzner who are a) paying for & would have to administer it themselves and b) is going to have access to all the managed services they would ever need in future.
I would still recommend they consider Hetzner for any high-resources intensive workloads where their raw compute is vastly less expensive. I'll also chose the cheaper reoccurring cost over convenience when I'm able to self-service it myself.