Perhaps the best thing to do is nothing? ; p
To me farming is a given and a pleasurable experience in this type of game. I have a desire to use a phrase I usually hate which is like, “Don’t fix what ain’t broke.” It’s a phrase I hate since it often discourages creative ideas, but sometimes the old formula is just working too well in a way that is likely to lose more appeal than gain it by attempting to mix things up.
Farming was pleasant even when I was farming Mephisto for the 2000th time in Diablo 2 with a level 92 sorceress who had little else to do left besides farm for gear and pick up the smallest amount of exp on the way. The reason it was pleasant is because, in spite of the repetition, I had a goal in mind to collect interesting, very useful gear. And in spite of playing the game for years, I was still surprised sometimes to see new drops every few runs that one of my 4 or 5 active characters could immediately use. There was a goal, and there was a constant sense of reward (not too frequent that it was too easy, but not too infrequent that it was getting hopelessly frustrating).
The pursuit was inspiring and motivational. IMO if there’s something to be improved, it’s the source of motivation and inspiration to farm, not the experience of farming. This game has a wide item database, but so many items do not really apply unless you’ve created about 50 different builds, all at different levels. Even with a couple dozen builds, I’d say over half the items I encounter in the game are almost useless to any one of them let alone the character collecting them, and that does kind of kill some of the joy of farming, replacing it with frustration as I see the same items I’ve seen a dozen times over drop that none of my characters even had use for in the first place. I lose inspiration more quickly in this game in the process of farming than Diablo 2 because of the nature of the loot. That doesn’t improve with increased drop rates, that’d just make me see more duplicates and items that none of my characters are interested in more often. If I see another pistol dealing poison damage I might go insane, such items are so, so, so narrow in applicability (a gun-wielding Occultist/X line? Maybe a gun-wielding witch hunter that’s not entirely a caster that put some focus into cunning? Not something I’m so interested in creating ever*).
* See, in D2 the creators could get away with introducing something like a poison-dealing bow without making it stash-hogging junk for the vast majority of users because it was not necessary for a build to focus on poison damage and get insane +poison/duration modifiers to truly benefit from it – any damage type other than physical was just a minor bonus in many cases. Because of that a lot of equipment that drops from armor to weapons to accessories could apply to far more builds than a very specialized one that someone even exhausting a lot of build ideas with dozens of characters wouldn’t have created yet. As a result there was a far greater joy whenever a unique item dropped, since there was a very healthy chance that one of your immediate characters could have great use for it. In GD, to encounter a single item that is applicable to one of your characters often requires wading through a seemingly endless pile of uniques that don’t. I realize that’s just a fundamental problem of GD’s approach to things (which maximizes build diversity to a greater extent than D2, but reduces the joy of collecting and farming), but some of the items exacerbate the issue by being already more narrow in utility than necessary. This is an issue completely independent of drop rates, even though many might see increased drop rates as the solution – drop rates are a red herring.
About trying to mix up farming and make it more fun, take someone who loves to collect stamps. I don’t share the enthusiasm but I get it. Is it really fun to go around shopping for new stamps? Maybe not, but a stamp collector is inspired and doesn’t think in terms of the immediate enjoyment, he has a goal in mind and he’s compelled to pursue it.
Would it make it more fun for a stamp collector if we started introducing obstacles in his way? What if I started throwing tennis balls at him to dodge every single time he goes shopping for stamps? What if I made it so he has to solve a puzzle or answer a riddle in order to get a single stamp? What if a store or post office selling stamps refused to sell him more stamps after a while until he went to another store? It doesn’t necessarily help anything. If anything, it might kill his joy and motivation. If we want to inspire and motivate stamp collectors more to get more involved in the experience, the obvious solution is to introduce them to very inspirational stamps to collect and minimize the junk stamps they collect on the way, not hurdles to mix up the way they collect stamps.
To me if the desire is to make the repetitive nature of this game less pronounced, farming is actually low on the priority list. For me, it’s questing. There is nothing that screams repetition in this game more to me than when I advance to a higher difficulty with an existing character or start a new one and end up in Devil’s Crossing, only to realize that I should save Elsa, collect fabric, kill Neegan, Jillius, etc., collect crystals for the inventor, dynamite for the inventor, scrap for the well, kill slith to restore the well, find Isaac’s hidden treasure, confront Direni, give slith necklaces to the Rovers, etc. etc. etc., for the 200th time. It is far, far more obnoxious and repetitive to me than Diablo 2 (which was still a little more obnoxious than Diablo 1). In Diablo 2 there were only 6 quests in a compartmentalized act (only 3 in act 4 IIRC) and most of them were “very optional”. In GD, while very few quests are required to advance, it compels and pushes you to do most of them when you have an active quest log appearing on the screen that starts to accumulate so many quests that it’s scrolling off the end of the screen if we try to ignore them and not even compartmentalized/filtered by each act. A huge chunk of experience is also gained by doing quests (maybe half or even more), not killing enemies.
That’s the part that screams repetitive to me, the repetition of doing the same massive number of quests over and over, not farming, since it ceases to lose its entertainment value a lot quicker than killing the same Nemesis for the 1,000th time or killing the same common enemy for the 100,000th time.
The heart of this game is hack-n-slash. It’s where it shines. You can’t really go too wrong making players hack and slash more and collecting interesting loot on the way while coming up with new build ideas. It’s all the things that get in the way of that and obfuscate that and make it feel less rewarding which will generally emphasize boring repetition a lot, lot sooner.
But i have my shared stash and 4 characters full of junk that has allowed me to level few other max level characters, and beat some of the toughest end game content with them.
