(This blog is probably 8 months late)
Advanced Warfare is actually a pretty cool game. It has a lot of unique features and brought a lot to the game with the exo movement + abilities, customisation and challenge rewards. Though like everything, it falls short in certain areas. The one area it falls extremely short though makes it the worst in the series in this particular place. Balance. This game is extremely unbalanced, and not like how people usually define unbalanced CoD games. It's not just that there are a few good weapons, it's that only certain types of guns are even usable if you want to do well. The biggest factors to this are that the game is pandering to a certain part of the community, the variants and even the Pick 13 in general.
For how many fun and unique guns they have in the game (NA-45, XMG, MDL, MAAWS, Crossbow etc.), they really don't make them that good. All the guns that are considered "good" or even somewhat feasible are all the assault rifles and a few SMGs, and this is because it was made with competitive/pro/pub stompers in mind. The top guns in the game (BAL27, ASM1, AK-12, KF5) are all the type of guns that competitve players would use. Fast TTK, high damage, good RoF and good range. If a competitive player wouldn't use an explosive sniper rifle, or a one shot rail pistol, why would anyone else? Everything else pales in comparison to the assault rifles in this game (except the MK14). All the fun weapons took over 8 months of patching to fix and make them as good as they really should've been at the launch. What do all the weapons that were bad at launch (EPM3, EM1, NA45, pistols, AMR9, MK14, S12, Tac 19, Crossbow to name a few) have in common? They're bulky, poorly handling weapons that the high scoring pro type players wouldn't even think of touching in a public match.
The variants were a fun idea at the start. A collectible to give your gun a new look and a new feel. Though pretty quickly, it turned into a race for the Obsidian Steeds, Speakeasys, Insanitys and RIPs. These are the best of the best variants for the best of the best guns. Once you got these, there was virtually no reason to use any other variant of the gun because you had the very best one. Not to mention that some of the changes were pretty negligible (+1 mobility, letting you ADS 1 frame faster at the cost of something else more important) or redundant (increasing the range but restricting any optical attachments/giving it less damage at range). It boiled down to pure luck to get this gun/enough $ to buy enough ASDs that you MIGHT get one. If they do bring back variants, the tiering system should be taken out. Instead, it might be better to make a variant that benefits each stat, but balance them out a lot more so people aren't all gravitated towards the +damage or +RoF variants.
Pick 13 System
The Black Ops 2 Pick 10 was great, you had so much flexibility and customization between your classes to do whatever you want. AW tried to take this one step further by giving you points to customize killstreaks for each individual class ala MW3. Though people took this as a chance to dump their killstreaks (which weren't really good to begin with) and add those 3 extra points to load up on perks or more attachments to benefit their guns. It was a good concept, but fell on its face in practice. It's best to keep killstreaks seperate, rather than giving them more points than necessary.
Advanced Warfare had so much potential to be good, and it is still living up to that potential even 8 months after release. But oh god the balancing is awful. You have almost all the guns designed around a certain part of the community, you have RNG super variants that make good guns and an easy way to exploit the points system to make your character even better. It might be too late to fix these things now, but Sledgehammer has such good ideas for their game. They've been learning with each of the new guns that are coming out, so hopefully that means they'll know a lot more for the next game they release in the cycle.