I guess behaviour may be more important in some cases, what with Meche having been assured a ticket on the No. 9 as a reward for all the charity work and whatnot she had done when she was alive, despite the fact she had little or no money.
Although I see your point, perhaps you can couple them together:
Good Behaviour + Money = GOOD
Any money could be used to opt for a better travel package, although having led a good life means you'd probably get a fairly decent one anyway, it's just they'd let you use money to opt for a better one because you have been good.
Bad Behaviour + Money = BAD
Just like when the people who have sinned or whatever try to buy their way out of the Land of the Dead with Double N tickets that aren't actually theirs. They've been bad, having lots of money wont save them.
So I guess money can be important, but only if its linked to good behaviour, by which I mean, having led a good life without sin.