So I've been running FB for some time but tbh I have never messed with manual bids, I just let it be at auto.
Can anyone talk me out of it?
I actually like the auto bids. My theory is that FB want you to be happy so you ultimately spend more money because your ads are performing well and your overall CPC (and cost per conversion if you have conversion tracking) is lower than you expected leaving you to plough more and more money into it.
But perhaps that's just me talking myself out of trying manual bidding.
I do think you need to spend time also improving the CPC yourself if you do go for auto bidding by split testing your copy and more importantly images and then also looking at the performance breakdowns to see which demographics are converting better.