Don't worry for one second about the tickets, or stage check. Absolutely zero negative impact. Lot's of folks here with zero TPIC. It seems you are actually in the sweet spot for getting an invite. As others have said, get a Delta pilot to give you a rec, and attend a recruiting evernt/WIA/OBAP/etc if you haven't already.

WHEN the invite comes, just be honest, humble, and turn any perceived weaknesses into a strength, i.e. "it made me a better pilot, and I've never done/missed X again". You'll be fine. Best of luck.