It's the same for me. I consistently saw worst performance numbers through Agesa releases. At this time, I really think PBO is not worth the hassle, it's a feature which rely heavily on temperature, and conversely as it needs to run at higher voltages to sustain higher clocks, it "throtles" due to the increased temps by upping voltage, so less performance. It's a chiken or egg question right now. AMD need to fix the set temps in the FIT curve if wants PBO would be from some interest to use.
As things are right now, I think the better approach to get the best possible performance out of Ryzen 3000 is to dial a stable CCX OC at around 1.325/1.350 vCore, targetting at least 4.4/4.45Ghz at the main CCX and at least 4.25Ghz on the rest. This way you get higher multicore performance than Stock/PBO+, and same single core performance, reduced voltages at idle, and roughly the same or a little higher temperatures, but without the maniac-temp-agnostic PB/PBO algorithm reducing your performance because a mere 5°C change in ambient temp.
Yes, I think vCore manual setting is broken for CCX Oveclock. Put it in Normal and use a positive offset instead Manual for now until Gigabyte can take a look at it.