A strong compliance record (entering and then leaving again) will go in your favour. Aside from that, it seems you don't have particularly strong ties, but that's not necessarily a problem. I have friends who've backpacked around the world and gone through the US with nothing more than a few clothes.

I was once berated by CBSA at YYZ for the audacity of entering Canada while being unemployed. I was still cleared off the primary line though.

One thing that's in your favour is, if anything does go wrong in DUB, you're in Dublin, and not potentially overnighting in a jail cell. Pre-clearances are a godsend for those who may feel anxious about their immigration experiences.