Some comments on the default rules that are generated with the new iptables module:
1- There's no more a failsafe ssh rule:
-A INPUT -p tcp -m tcp --dport 22 -j ACCEPT
this can be dangerous , I 'd keep the option that inserts it and enable it by default
2- There's not a rule to manage ESTABLISHED connections:
-A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT
-A FORWARD -m state --state RELATED,ESTABLISHED -j ACCEPT
I've always considered them safe and useful