Interesting names AuntDympna.
I'm not sure that the phonetic English spellings you've given are quite accurate, though of course I don't know how these names used to be pronounced, and they're not commonly used today. For example óg is not pronounced as o in modern Irish (it translates as young and is still used in names sometimes, Seán Óg roughly translating as John Junior, literally young Seán). I don't know how to write it phonetically, but there's a g sound after the ó.
Re Lonnóg - lon dubh (blackbird) is said lun duv, more or less. So the o in Irish is more like an English u than an English o in the word lon. However, the root word in Lonnóg is lonn (which translates as eager, bold) not lon, so maybe the reference in the name isn't to the bird at all? Lonn is pronounced the same as lon in at least some Irish dialects, but maybe not in others (my Irish isn't good enough to be sure I'm afraid.)
forvo.com/word/lonnóg
As I said, this is in modern Irish though, the names could have been said differently in the past.
I quite like Féimhe, which I would say as Fay-va (don't know if there should be an m sound at all?). I also like the sound of Life in Irish, but it would be unusable these days I fear.