Nevermind on the chocobo. Apparently Chichu the ochu is by far the best monster member.
Other tips I've come across so far that might be useful:
-If you recruit a sentinel (like a Pulsework Soldier), and you pump a lot of HP upgrades into it, they have ridiculous amounts of HP for tanking.
-pay attention to your monster's passive abilities. Some of them may not have as good stats as others, but they might have really useful passive abilities like Item Collector (increases rare treasure drop rate) or Gilfinder II. Like Caith Sith is a good medic, but I use a leech as my medic because he boosts my rare treasure rate by at least 110%. Just have to make sure he's in battle at the end.
-On the Crystarium, its best to progress all the roles as evenly as possible, rather than just focus on one or two. The exception is to be careful what role you use the large nodes on. For Serah, you want to use the large nodes on Ravager, or SAB (if the current level is even), or SYN (if the current level is even). For Noel, you'll want to use large nodes on Commando, or SAB (if the current level is odd), or SYN (if the current level is even). That's the best way to maximize your stats.