are you familiar with the app_config.xml files and that you can configure projects beyond the settings withing the project? Although iirc Yafu lets you set core limits within the project but you can for example tell a projects application how many cores to use per the application , for example you could tell it 8 cores and you would end up with 5 yafu 8 core WU running at a time. Also , if you look at the properties of work units you will see that there are for example 1,000,000 clock cycles on 1 and maybe 10,000 on another thus making work unit times different but credit is credit and its not based off how many work units you complete its based upon clock cycles that you contribute. Originally it was bogomips back when we were in the AMD K6/K6-2/K6-3/Slot 1 days of seti@home and a work unit took you 5-7 days.
You can also configure your GPU for more than 1 thread.
Here is an example , and you can google " boinc app_config.xml " along with " boinc plan_class "

Since steemit wont allow me to paste the .xml examples correctly without wanting to use html code tags here are some older configs for examples http://xion.dopeshit.net/~blah/boinc/configs/Configs/ and what I am talking about and you can find examples along with write/do this on every project and for every application.