The Hue bridge app using lots of resources (CPU and/or memory) has been an issue for years now. I don’t think Athom was ever really able to solve it (it works for “most” people, so that’s good enough for them, it seems).
In my case, in the past the app was known for consuming quite a lot of memory. Which is ok at the moment, know it is consuming a lot of CPU and traffic 
I’m in contact with the support and provide some resources…we will see if its changing in the future…but if nobody “complains”, nothing will change for sure 
Seems indeed that when u kill the Hue bridge app it runs a lot better. Still wonder it has something to do with the load because my load is low anyway:
In my case i use three Hue bridges with 89 devices.
Meanwhile i deleted all Hue lights within the Homey and just speak to Hue lights via scenes.
Works better in my case, the load is now at round about 60-70% coming from 300-350%.
And i will have a look at the wifi traffic the app creates during the next 24h. Hopefully the traffic will decrease, too.
Ok cool. But deleting my Hue bulbs is not an option. Whish they go fix issues instead of adding Alexa/Google flow starting thingies and hoping they get lots of likes at Facebook/Instagram. What the frack is going on in their minds?
“If we can’t reproduce a problem, it doesn’t exist”
