Woah haha thank you to both of you and apologies for the late response !!!
I really appreciate both of your in-depth answers, and will definitely be looking more into every topic. I do like the appeal of the bovedas, and was looking as much as i could into those, though i can't understand spanish so it was a little hard, but thank you Simon ill be using some of your explanations to research it even more.
About the legality, to be honest i have no clue how the legal process of this works in ROI (Republic of Ireland) but i should look more into it than i have been. I suppose i assumed there would be very little trouble as cob houses are obviously common here and i figured if they can approve thatch roofs made hundreds of years ago they would approve of a newly constructed boveda, lol.
So, i'm pretty sure i'm leaning towards a boveda style of roof, and like you said i'd have to include a concrete ring to help with stability and such, if i'm understanding correctly. Would the limecrete-like-method work on a boveda style roof, and would it also be applicable to a place where rain is so common?
Thank you again Phil and Simon, i never would've thought i could've received such incredibly helpful and in-depth responses ! It helps so much, truly.