Did you ever move away from Amazon CloudFront in the end @scottfsmith ?
I’m finding myself in a similar boat in terms of rising expenditure.
CloudFront is quite new to me. I’ve been running only an S3 bucket for the last few years but based on recommendations here I setup CloudFront last month.
All this has done is move the cost away from S3 data transfer and over to CloudFront data transfer instead, the total monthly bill is still the same.
I find myself approaching an unsustainable monthly bill for data transfer.