Running the entire FRStack Node Red flows takes about 25% CPU between NodeRed and DotNet on my Raspberry Pi Model 3B Plus
By no way do you need to run all of the flows. Just run the ones you want.
Also I have the polling fast so you could slow down the nodered flows.
# this will report your model
cat /proc/device-tree/model
# this will report your CPU info
cat /proc/cpuinfo
# this will show running processes
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