I feel it would go a long way if they removed the only one CE chain at a time restriction. I get why it was implemented initially but with the way CEs scale now I don't think CEs failing is as much of a concern as they used to be. At least maybe 1 CE at a time per subzone if the restriction is absolutely necessary. Even if you spend the entire time killing scorpions with the way it works currently it can take over 2hrs for the CE chain to spawn and there is absolutely nothing you can do about it which is extremely frustrating.

Probably wouldn't hurt if the cooldown period was reduced significantly as well. Same with the cooldown period for fates/NMs in Eureka now that I think about it. So much arbitrary and pointless waiting.