This are the things I look for when looking at carriers. I’ve gone through over a half dozen and then some over the last 20 years, and my requirements update as time has gone on. I will also cover some of the personal “whys” in the equipment I selected for the carrier shown.  
This isn’t an end all be all video on carrier setup, but a thorough look at the items you should consider when selecting the equipment to build out your fighting load with a plate carrier.  
Training:  
https://www.maneuvertrainingsolutions…  
https://www.oriontraininggroup.com/  
 
Gear:  
https://www.refactortactical.com/prod…  
https://www.first-spear.com/multimag-…  
https://esstac.com/  
https://www.spiritussystems.com/  
https://ferroconcepts.com/  
https://www.aandatactical.com/  
https://shaw-concepts.com/  
https://www.axladvanced.com/