The entirety of the problem with Destiny’s design comes from two factors - the seamless drop in drop out co-op, and the investment system.

It seems Bungie wanted two things the make Destiny special: public events and journey style co-op. This necessitated creating the levels in a certain way. You need to design areas in which players would frequently run into each other on. If the levels were like Halo, long and linear, then there’d never be a spot where you’d run into someone else since everybody would be playing from beginning to end, then moving on to the next one. Bungie seems to have designed the spaces to ensure players meet - they made a few large exploreable wide open type areas, and the missions and patrol mode frequently have players going over the same locations repeatedly.

So while enabling the “shared world” aspects of Destiny, it’s a severe detriment to the actual missions and to the world as a whole. In terms of world building, it just makes the game feel smaller since all this stuff is happening in the same space. Rather than do what Halo did and have unique areas for each mission, all the missions have to happen in the common areas. If you look at The Dark within, you make your way from the cosmodrome landing point to the inside of the skywatch and destroy the moon wizard. Then, you do the Warmind, and you start in the exact same place as the Dark Within, and you trace the exact same path! You make it to the same room in skywatch, you just go farther. With so much repetition of space, everything feels smaller.

Bungie would have been much better served if there were 12 Reach sized levels, each designed completely for story encounters, and each a unique space. This way you could not only go to Old Russia, Chicago, Mumbai, Venus, Mars, and the moon, but to Mercury, Io, Europa, the Asteroid Belt, Phobos, Titan, etc. Same total amount of geometry, but make it more dense in terms of player engagement. So much of the space in Destiny is wasted because you are just speeding across with your sparrow. So much of the space in Destiny is wasted because it’s wide open designed to facilitate Journey style co-op. So much of Destiny’s space is wasted because it has to fit to many missions, which is why there is no variety other than bringing your ghost to a location and defending, instead of scripting encounters and designing spaces specifically around unique encounters. So while in terms of actual geometry it is huge, it not only feels smaller, but is less engaging (and makes the story feel smaller too).

So while designing a more typical fps campaign would have solved the issue of mission repetition, you would have to give up on Journey co-op and public events. Would that be worth it? The answer is a resounding yes. I feel like both of these things are merely novelties. Public events are a bonus, but ultimately just a minute or two of fun. If you get an eliminate the target one, everybody skips it because those are terrible. Running across other guardians is alright, but because there is little way to communicate it ends up functionally being no different than if they were AI bots. So all the concessions that had to made were not worth the tradeoff, since the hyped up “shared world” elements do not add much to the game, and the part that’s fun (the co-op) is just online co-op that Halo 3 and many games have had since. The loudest complaints about Destiny are that the social aspect is severely lacking, so those elements didn't even do what they were envisioned to do.

Likewise because of the investment system, Bungie needed a larger number of missions. If they only had 10 big ones, then daily mission bonuses would start repeating pretty quickly. People are more likely to want to repeat something short for gear bonuses than something long.

This right here is why Destiny is lacking, and why reviews are bad. These two selling points of the game not only are not that great or revolutionary in and of themselves, but their inclusion requires compromises to the level design, and in FPS games level design is hugely important. I feel like in most MMO games, level design is tangental because it’s just a place to fight, but in FPS it’s the space you are navigating and using against your enemies. So while the shooting mechanics in Destiny are great, there ends up being a lack of creative and compelling level design which hurts the game substantially.

Bungie can’t back out on it either. This is how Destiny has been build, and it’s got to continue that way for the next ten years. This is why you don’t bank on one thing like that. They lose the ability to change around what works and doesn’t since they can’t abandon the core of their game. It’s unfortunate. The only way things might change is if nobody buys the DLC and votes with our wallets. If the DLC is just mission packs and no new level areas, this is what should be done.

The other problem with the design is the way PvP and PvE are intertwined. This is fine if you like both, but if you like only one you are in trouble. If you only like PvP, you are more or less forced to play PvE since that’s the easiest way to get good guns. Even though the damage is normalized, gun skills and things like stability / rate of fire are not. Unlock outlaw on your gun, and you will reload much faster after a firefight than someone who doesn’t have a gun with that. If you have a beast of an autorifle with high impact and stability, you will school fools with bad ones. What you bring in matters a huge deal, so whether you like it or not you must engage in acquiring weapons.

I feel like Destiny PvP should have worked like Halo 4, with selectable loadouts for everybody, and have Iron Banner be where you bring in your PvE guns. I like both so it doesn’t impact me as much, but there are times you are fighting with people who have shitty guns and just have no chance against yours.

No voice in matchmaking is shameful. If I go into a strike playlist, I should be able to hear my other two teammates. If I go into the crucible, I should be able to hear my team. If I invite someone in the world to my fireteam, they should join without having to drop back to orbit and reload. Players whom you do run across in the world should not phase out of existence when you cross a loading barrier to a new area.

Lastly, the investment system sucks big time.