Romans in Ireland?

[Scipio Bristolus]

If, as stated, Ireland was largely pastoral, then it could, like parts of Germania and those other damp, forested places, prove too costly to bother conquering? In that there are few population concentrations i.e. not enough strategic cities to take and hold to control trade and revenue in relation to the likely income from the place. So the bottom line is the balance sheet rather than anything else?