If I have two complaints about anu Gundam series they are as follows:
1. The Pilots of the Gundams
---They are always children and can't fully understand the hardships of war along with many other negatives young pilots bring on.
2. The Gundams
---Arguably the best Gundam is 08th MS Team which used Gundams more as advanced mobile tanks, they weren't severly overpowered and actually used tactics. The best parts in gundam 00, ofr me atleast, have been Sergei Smirnov's attack on the Gundam mobile base. Mainly because that actually used tactics and represented space as space with no gravity, something 00 consistantly fails at (people don't stand up strait with no gravity, people have inertia). The second part being Ghrahm's recent assault on one of the Thrones where he used his brain and skill to defeat them. Gundams are always way to hax powered, no tactic, just throw 4 of them into any situation and they'll kill everything with no tactics planned before hand.