Hi, Veni. There is some latitude for regional and country projects to organize higher level categories in ways that make sense for them. While I was not involved in creating these categories, I know that in Ireland the two predominant faith institutions are the Roman Catholic Church and the Church of Ireland, so I can understand placing those names first.
The most important categories are what I call the "landing categories" -- the categories you actually want profiles attached to. These are consistent in Ireland with other places, namely Name of Faith Community, Local Place, Regional Place. I say this because it is relatively easy to re-name and re-organize higher level categories, but much more difficult to re-name "landing categories" because the category has to be changed on each profile. So that is the most important one to get right.
In looking at categories, it's always important to ask "what genealogical purpose does this category address?" In the case of faith communities, they have historically been repositories of records of significant life events and relationships. In addition, people tend to be members of faith communities as families. Both of these considerations make it worthwhile to categorize individual profiles according to the local faith community they were a member of.