The grind from 20-30 definitely took a bit longer, but it wasn’t too bad. You just had to be smart about where to grind/level. If you are being ganked in the Abyss while trying to PvE grind out levels and points, it doesn’t make sense to keep going back. Although the Abyss does reward higher experience, higher DP gain, and Abyss Points which becomes an incentive for players to travel out there. Coin and Campaign quests are usually worth doing since they reward items and/or good experience.
So now with a level 30 character, you will automatically receive a quest for your Daevination gear. You will have to buy a “Holy Item” from a vendor for about 98,000 Kinah and turn it in for a nice blue quality item. Once you receive the item, you will notice that it is part of a 5 piece set and has bonuses depending on how many pieces are equipped. The catch is, each character can only do this quest once, so you must have 5 alts at level 30 if you want your main toon to have all 5 pieces. This is usually not worth it but it does reward those that choose to re-roll. You can do a quest to have the item transferred to another one of your characters and it will even change the armor class. Now if somewhere in the future you were ever to obtain all 5 pieces, you can continue the questline and turn the 5 pieces in for a Daevination Weapon for your class.
Level 30 also allows you to remodel items to look like other ones. Be warned though, the item you are taking the skin from will be destroyed. Since we were disappointed in what our crafted Twisp/Fess set looked like, we remodeled them. While exploring our major city, we came across a vendor that sells vanity items such as X-mas outfits. So we picked out a 5 piece set that we like the skin of and remodeled all our gear while destroying the vanity items in the process. Now if you want to reverse the effect of the remodeling, you will have to buy an item from a vendor for around 30,000 Kinah to do it.
At this level you also can equip the level 30 Collector’s Edition wings or the green quality ones from the vendor for around 950,000 Kinah. This will add 30-40 seconds to your flight time which is a huge deal when you are collecting Aether and generally reducing the number of stops to your destinations. If you are holding off on collecting Aether, we recommend waiting till you get these wings to make the process of leveling it less painful.
While leveling up gather skill, you definitely have to spend some time on it. Even if you pick up everything you see, you will still have to go back and actively level it. It isn’t so bad if you keep leveling your character and gathering separate. You can just go back and collect from nodes that are bunched up together while doing something else like watching TV or something. It became important for us to do this separately because taking advantage of the 10 minute DP pet buff speeds up leveling considerably. For other classes you could also try a combination of the two and gather when you are running low on mana/health and just want to regen passively.
As far as currency, we have 1.2 million Kinah and have expanded our cube 6 times and warehouse 5 times. The 5th cube expansion is done through a level 29 quest in your major city and is free. The 6th upgrade is located in the Abyss on and island in the middle of nowhere.

One Comment(+Add)
You can expand your cube a 7th times by a quest in Heiron (Elysean side)
Dunno how to do for Asmo.
http://blog.me0w.co.uk/aion/2009/10/02/the-cube-%E2%80%93-expanding-your-inventory-in-aion/