Your absolutely correct Mikey...
The 22t heads have tiny valves, tiny intake and exhaust ports, the cams aren't that great, and they can't rev.
The ej25d heads are the solution for better performance on a budget build.
However, I am not shooting for max power with this build.
One thing that is important to me with this build is simplicity. I am doing everything myself and I appreciate the simplicity of working on a SOHC engine versus a DOHC engine.
I am only running 5psi out of a TDO4, and a rrfpr. This is the classic build that everyone will say... that is the half assed way that won't make power and won't be as reliable/sophisticated.