As a company director you are not entitled to claim the Paye tax credit, you do however pay a reduced rate prsi, and have greater access to expenses than most employees. In my oppinion the Paye tax credit is attempt to create equity between self employed persons / company directors and paye workers.
A small company can opt to become an annual remitter for paye/prsi purposes by sending a faxed request to the collector general on 061-488673, the CG will either approve or reject the request based on a number of factors including whether or not the company is tax compliant etc.
The optimum setup for paye/prsi payment is a monthly direct debit with revenue, it is not neccessary to submit the monthly P30 when the DD is in place thus reducing administration, and the effect of taxation on the companys cashflow is more accurately reflected.
I hope this helps,
regards,
Ikeano