One thing I think Glitch could benefit from is by adding achievement based advancement options such as those seen in the cooking skills to many of the other skills we have. What I am talking about are things like having to cook a certain number of items with the awesome pot to unlock some of the better dishes you can make such as awesome stew.
This makes it so that a person who has spent months cooking with his Master Chef skill has something to show for it. He can make dishes that the person who has just gotten the skill and never used it before can't. It helps to give people a sense of accomplishment and advancement within a skill rather than giving them everything the skill has to offer right of the bat and it would be a great way to add to other skills that don't have this built into them.
For instance adding some new potions to the potions making skills that become available to people with the advanced badges in the skills would be something nice to work towards. It would take much programing, the new potions could even be just improved versions of the regular ones like a rainbow that lasts twice as long, or poison that kills faster, or animal youth potions that have an extra few doses.
For the teleport skills you could do things like adding an extra destination slot to the menu for people who have some of the more difficult badges in this skill or increasing summoning and map teleport limits by one for tele 4 and tele 5.
There are very few skills that one couldn't add a little content to without a lot of programing that would add a sense of further achievement and advancement within those skills so people have mini goals to work towards while they wait for new skills to come out.