These are the wrong metrics to look at.
CTR doesn’t really matter if you’re using amazon or someone else since people clicking the link don’t necessarily pay attention to where the link goes. Which is to say CTR depends on your site, not your affiliate program.
Earnings per click is more important than CR. People report really high amazon CR because amazon reports CR as: # of items / # of clicks. Every other program in the world would report CR as: # of orders / # of clicks.
So if someone comes in and orders their weekly groceries on your cookie you’ll report a CR of something insane, but you won’t actually make any money since it is 1% of a bunch of $2 items.
Anyway, my point is, you should look at how much you earn for every click you send to amazon versus alternatives and then direct your clicks accordingly.
But, to answer your question I get a CTR on my primarily amazon sites of around 80%, and a conversion rate of around 15%. But that varies a ton from site to site and EPC varies... anywhere from about $0.12 per click to around $0.35 per click depending on the site.