I am flying to HND on AA, arriving 6:25pm. Want to take HND-KIX on JAL (separate ticket) either last flight that day (8:55pm) or some time next day.

1. Is 2.5 hours enough to connect on separate ticket?
2. Can I check bags through to KIX with AA?
3. This page says "If you have purchased JAL domestic flight fare from outside of Japan, you can check in ... up to 2 pieces weighing up to 23kg (50 pounds) each in Premium Economy Class/Economy Class, free of charge." But this page says "Up to 20kg is free of charge for each passenger." Anyone know which rule would apply to a JAL domestic flight booked with AA miles outside Japan?
4. Each of us will have 3 roller bags (2 check-in, 1 carry-on). If staying in Tokyo overnight (and going to KIX next day), how inconvenient and expensive would it be with those bags? Could we store them in HND overnight?

Thanks.