Possible big effect: Richard I living longer and being successful in Normandy --> John does not suffer defeat at the Battle of Bouvines --> No (weaker?) Magna Carta
No bouvines has a lot more repercussions than that. No alliance between John and Otto has a major effect on otto's war with Frederick, no bouvines means that the (relativly) undisputed hegemony of the french crown is delayed or averted, etc...