About this phrase

Ba is the Conditional Mood / Past Tense form of the Copula. It lenites.

Breá is an adjective meaning fine or excellent.

Liom is a prepositional pronoun, meaning with me.

Thus, ba bhreá liom: I would love [to] (literally, 'it would be fine with me'; but note that the 'fine' here is somewhat stronger than in English phrases such as 'that's fine by me').

Prepositional pronouns formed from the preposition le

• liom: with me.
• leat: with you.
• leis: with him; with it (masculine).
• léi: with her; with it (feminine).
• linn: with us.
• libh: with ye (plural).
• leo: with them.

The same prepositional pronouns' emphatic forms

• liom-sa: with me.
• leat-sa: with you.
• leis-sean: with him; with it (masculine).
• léi-se: with her; with it (feminine).
• linn-ne: with us.
• libh-se: with ye (plural).
• leo-san: with them.