I'd suggest that you should keep the ''parent of Irish citizen child'' option as a back-up (in case if anything goes wrong - which hopefully will not in your case).
My brother is thinking about apply for parent of irish child, as he got a letter from Immigration asking for 2 years history for his EU spouse ( scary!
)
I asked the immigration council and they said that my brother will have to apply for the parent of irish child status and the application might take a good few months.
So I think and suggest that you should go for the PR and eventually get either PR or citizenship application approved.
Some of the parent of irish child cases are complicated. It says on the website that someone who has current permission to reside in Ireland can go to the local immigration office, however, if the case is complex, then it is advised to apply using the application form.
You can still try and go to the local immigration office and see what they say.