That's a tricky question. Both have their benefits. In some apps the tighter timings helps more than the speed, but only to a point. And the same can be said in reverse.
Your DIMMS obviously have an XMP setting, so you could try Ryzen dram calc here :
https://www.techpowerup.com/download/ryzen-dram-calculator/
It's useful in that you can import the XMP profile (just follow the instructions) and get the best timings available at a given speed for your DIMMS. This will give you the best of both worlds, and all you have to do really, is input the timings manually.
Clearly it's best to have both tight timings and the most speed you can eek out.