I don't know if I can recconmend the DLC or not but just for how many Negatives I'm going to add in this Reivew I'll just make it a not recconmended reiview.
The upsides are this DLC gives you the power to make adventures in a world similar to the Creature stage, You can also use the things you used in combat as a creature and the things you used to socialize.
It is recconmended you start with the Social missions first so try to avoid missions such as Temple of Spode and Infestation until you get weapons (One type of various rewards you get each time you level up) and if you want the Full-On package you'll have to download Creepy and Cute parts so you can get even more playable missions, otherwise the creatures you will find that have Creepy and cute packs will be replaced with some of Maxis's Creations.
(That's kind of a downside seeing you need to spend more money to get access to certain community made Adventures)
The Downsides are the amount of Adventures made by people that have no idea what they are doing and trust me there are ALOT of those missions and you're probably going to end up with plenty of them when It automatically downloads creations for you. (You can get some pretty decent Adventures though if you're lucky)
You're also probably going to have to give your creature high stats on about everything and give them the ability to jump because most adventures don't support that and you'll probably get stuck on one step, That's also one thing you have to keep in mind if you want to make an adventure where anybody can play as ANY creature, or if they haven't god jump boosts yet or you should make a little warning about it at the beggining about Obstacles or parts they wont be able to beat without a certain feature.t
If you want to make an adventure you'll have to put alot of effort into it if you want everybody to like it, Which is a bad thing if you haven't got the time.
TL;DR version: Upsides: A whole new way of playing Space Stage and the Ability to make adventures to entertain other users.
Downsides: There's going to be alot of trash and I mean alot of trash, Not ALL adventures will be compatible with certain creatures so keep that in mind if your creature cannot fly or jump, You'll have to put some effort into an adventure if you want others to enjoy it, Which is a downside for people that are too busy.