If your business is based in Ireland and targeting a mainly Irish demographic then it would be advisable to also register the .ie domain name, this will also help your search engine ratings i.e. if someone is searching for an Irish business or is searching from within Ireland then the search engines will recognise that .ie domain websites are the most applicable results to return.
It is relatively inexpensive to register the other TLDs you have mentioned so it would be a good idea to register them now while they are available rather than waiting until your business becomes well known at which stage someone else may have registered them, if that occurs you will find that the costs to get back the names are much higher, and the chances of success are not guaranteed, i.e. if there is another business with a similar name or service they are probably as entitled to the domain name as you are