Least Expensive Exchange Fees

Based in the US and fine with KYC. I had always used kraken but they recently increased maker fees to 0.4% up from 0.25%.

I am an infrequent buyer, maybe a few thousand per month so most likely do not qualify for reduced rates based on volume.

i had looked into strike and river but the lack of transparency around spot pricing and order flow was concerning.

any recommendations?