We're in a pre alpha state. Let's implement it first, get a whitepaper out and then talk about review and audits.
"External" audits of unfinished stuff make little to no sense.
You don't need even one line of code to review the idea behind POI.
In fact,
reviews and designs are done before coding starts so that if there are problems, they can be fixed
true
but... in some cases it needs coding to make at least simulation to know, how the system works and how the data flows. If such test results need improvements, then the design may be changed or parameters modified or ...
For example in the case of NXT the simulation could have been used to find out, how the forging works and how it distributes the fees. That was not done - at least nobody had written so. (Or was that too obvious, when that has been asked few times

)