First of all, congratulations on completing the course!
Unfortunately I don't know what level getting to the end of the tree on Duolingo makes you, but I think it's certainly not A1, as your profile states :) Anyway, I'm just a fellow learner of Irish, but think I have something to recommend. Try "Speaking Irish / An Ghaeilge Bheo". It's a workbook (+DVD or CD) designed for intermediate and advanced students. Every unit consists of an interview with someone from a Gaeltacht (I think it's extremely useful because you have to familiarise yourself with a variety of dialects anyway, and these interviews are pretty authentic so they are great for listening/comprehension practice), its transcription, notes and explanations in English. I don't find the material easy, but I wouldn't call myself an intermediate student of Irish either, so I guess it's not that surprising. If you have a B1 level or so, I'm sure it would be just fine for you. If you need some files, send me a personal message, I'll give you the links.