I dont know about you, but I like playing different armies. I dont like playing yellow marines, red marines, black marines or grey marines. I prefer to play the Imperial Fists, the Blood Angels, the Black Templar, and the Grey Knights! The variety of armies in 40k is already quite limited, and yet there are still things that keep the armies separated. One sub category that is hard to keep separated are the armies of the space marines. Each space marine chapter is supposed to be unique, yet similar, but their strategies and tactics can be quite different. Because of this, I like seeing a variety in playstyles amongst the Astartes, as well as other armies. It would not be fun however, to see every darn army out there with a Stormraven or three, knowing that the only reason why people field it is becuase they can. I dont want to see all ork armies with the same style of play, nor the same nids armies as well. I most certainly dont want to see space marines all played the same with the same tactics and styles. There are MANY different things available to the Codex Astartes chapters, that there is no reason for any of them to look the same. Plus, they dont need to have the Stormraven just becuase some non-Codex Space Marine chapters do. If all the armies looked and fought the same, then this game would eventually be nothing more than tic tac toe, in which everyone knows what the next player's move will be before they have even done it. I like playing Space marine armies with jump packs, or a fleet of rhinos, some with a massive amount of devastators or an all drop pod army. I like seeing blood Angels with Stormravens dropping off Furiosos and the Sanguinor, while their Grey knight counter parts use their Stormraven as a teleport homer to bring a Dreadknight onto the table right next to it. I like seeing the variety that comes out of proper codex segregation, and the fun that you have when you think "cool, I'm playing a Grey Knights or Blood Angels army and not just a grey or red space marines army."
Of course, any dedicated 40k person must never forget the story line or "fluff" and how that influences the gameplay and tabletop performance of every army. According to their respective codices, the Grey Knights and Blood Angels have been using the Stormravens for a long time, and the tactics involved with the Stormravens mimick the tactics used by the Grey Knights and Blood Angels. Both armies tend to be first strike oriented, trying to close the gaps, and getting into combat as quickly as possible. They are able to be tactically precise due to the shaping of their army rules and the fact that they are able to use the Stormraven to get across the board rather quickly. Most other space marine armies, such as the Imperial Fists, are siege oriented, and have no need for a Stormraven. Why should it be possible for them to be able to use the Stormraven if it doesnt even fit the fluff of the army? I am just waiting for people to complain that the Dreadknight or Furioso dread needs to be made available for all the other chapters as well. If Games Workshop wanted to give all of the space marine armies the same units with slightly different rules, then they should of just added them to the main space marines codex and just put excerpts in there for the army's special rules, much like they did with the Salamanders, etc. But, fitting in with the storyline once more, the Grey Knights and Blood Angels do not follow the Codex Astartes, and because of that, they would not use the same units or have the same military organization as their Astartes brothers. I know people like the Stormraven, but does everyone else really need to have one? The Grey Knights are supposed to have access to the most advanced and ancient weapons in the galaxy, setting them apart from their battle brothers. So why then should every army have the same things as them? Wouldnt that just ruin the fluff? Besides preserving the storyline, making sure that not all armies have the same units and similar rules will keep the game from becoming stale and unappealing.
Stagnation through similarity is never good in the gaming world, and it certainly is not good in the universe of 40k. The last thing we want is to lose interest in something that we all have sunk (or will be sinking) a lot of time, money, and energy into. The desire to keep the armies different should be key amongst not only the game designers but the players as well. In order to protect against this stagnation, and preserve the FUN, excitement, and challenge of the game, we must keep the armies balanced but different amongst each other. We must keep army specific rules and units intact, ensuring that each army will have a different feel, spirit, playstyle, and attraction. Preserving army specific rules and units help keep the armies different, meaning that instead of always playing the same army, we can have some variety and different challenges presented to us by fielding and playing different armies. Some of these armies are completely different species, races, or chapters, none of which should be duplicated, otherwise it wont make a difference fielding a Tyranids list from Necrons, or Black Templars from Blood Angels. Not every army needs to have a Stormraven, a Furioso, Carnifex, Weirdboy, or Monolith to be competitive and balanced. We are playing different armies for that very reason, because they are DIFFERENT, and that is whats fun. I know that a lot of space marine players think it is unfair that the Knights and Blood Angels get the Stormraven, but look at what they DONT get. I cant speak for the Blood Angels, but the Grey Knights dont get the Vindicator, Predator, Land Speeder, Drop Pod, Thunderfire Cannon, Whirlwind, Bike units, etc. I am not trying to say that they should have them, because I feel like those units are unnecessary, but I am saying that I think its ok for them to be one of the only armies to have the Stormraven, I think thats a fair trade. Ultimately my opinion matters only to me, and I'm sure there are many out there that want the Stormraven to be released for everyone, regardless of the things I have mentioned, and that is fine. I only hope that the game continues to be as fun as it is, and that the armies remain as unique and different as the people who field them. In the end, it doesnt matter if you have one Stormraven or none, as long as your having fun with your army then thats all that matters!