Now that I think about it, some of these ideas might be pretty well suited if they were to return.
Neodrives
While at first it may seem a bit unfeasable, maybe if they limited it to accounts over 1 year old and with owners of at least 13 years of age, TNT could probably scrounge up a couple of megabytes of space and bandwidth per users (as long as the files and images weren't able to link to websites other than neopets.com) Or it could be a Premium feature? That'd be reasonable I think.
The Marriage/Gang/Friend Group Pet Issue
Marriage, maybe not, but having friendship groups, just groups, could be possible. Being able to set a status you pet has with other pets, like
"
Pet123 is a
good friend to
Petabc"
"
Pet123 is an
arch enemy to
Petabc"
Whilst probably having no real value or even adding any significant features to the site, something like this would be pretty cool. It'd give the pets just a little bit more personality, and give the site just a little bit more depth.
Discount Cards
I was never around for these, but maybe TNT should offer them up in competitions or as prizes for LCs, Mystery Pics and Random Contests?
Billion Neopoint Giveaway
We need something like this again. And it'd be a great way for TNT to make some extra revenue from sponsors
For everything else... no comment.