I noticed that the word áitiúil contains áit, "place". Does the iúil part of this mean "nearby" or something like that? (I like etymology, needless to say!)
Not necessarily less (I mean, how can you quantify the number of nouns in a language? Especially with constant coinages), but the default is to assume a noun is masculine. So, if you don't know the gender, treat it as masculine.