According to google documentation, I supposedly should make more money if I use their recommended ad units for my website, and the smallest one I can find is 320x50px. Because I'm optimizing for older devices, I only have a limited screen to work with (about 320x240px in size).
Placing the ad near the top helps with income but at the same time, it causes alot of content to be pushed below the fold because of the ad height relative to the screen height which in my case, it takes up about 25% of the screen height.
My other option is 160x600px ad unit but that creates further problems because that unit takes up half the screen horizontally and I need to fill up an area of the same size with only text but I don't feel I have enough text. On top of that, the ad unit causes users to scroll to see the whole thing.
I looked at options and I did notice a 180x150px ad unit that I could use but it is not in google's recommended list. Same goes with custom defined sizes.
Google recommended responsive size, but at the same time I'm not allowed to use it because I have a separate desktop and mobile site and its against google's TOS.
So my question is, why can't google just recommend a smaller ad unit so I can wrap text around it and make the site display nicely (by wrapping the ad in with the text) on ALL smartphones including those that were created years ago?
I don't mind if I have to use tables for layout, but I'm now starting to see that google wants alot of content above the fold and in order for me to achieve that and to try to make good money, I have to wrap ads with text and its hard to wrap text around a 320x50px ad unit.