It all depends on how the game does the grinding. And by far, Grim Dawn is not too bad when it comes to Legendaries off all the games I’ve played so far. I’ve got tons of Legendaries, although none of them is one that I want. Making most of them drop everywhere is a big plus because that means you can go revisit a lot of places instead of doing the same boss over and over. So, it’s not that annoying.
The only problem is that the more Legendaries you add to game, more harder and time-consuming will be to find the one you want. But that’s a natural consequence, and can be easily solved by just tweaking up the drop values a little bit, in my opinion.
Monster Infrequents, on the other hand, need a second look and a serious overhaul in how to obtain them.
The thing is, items that have random affixes and associated bonuses are not new in games like these, but they were always been intended as placeholders until you get better stuff and as a mean to get cash. MIs (and rare affixes for that matter) are different because they are items that already have a few stats and if rolled with the right affixes they can have practicaly the same quality as a Legendary. And since some Legendaries are not compatible with each other and/or even made with specific staples in mind (I mean, most heavy armor tends to benefit better either Soldier or Demo, and caster gear Arcanist/Occultist/etc.), MI and other double rare greens are the way to fill gaps that you feel a Legendary will not cover.
But “IF” is the key word here because you are not fighting against one dice roll like Legendaries, you are fighting against three. You need to not only have a chance to drop the MI, but you also need to cross your fingers to also come with the affixes you want. And it’s not just one affix it’s two, meaning that you can drop one with one affix you want but chances are it will come with an indesired one, and them you get one with the other you want, but will come with another bad one. (or even none)
It’s almost the same problem with Runewords from Diablo 2. Good idea on paper to allow the creation of unusual builds for a particular class, but not only you need to farm the right runes, you also need a piece of equipment with the right number of slots, no more no less.
To make a long rant short, the “dice roll grinding” of Legendaries isn’t frustrating to me, and if it goes out-of-hand due to the increasing number of Legendaries, it can be simply solved by tweaking the drop rates. Monster Infrequent/Double Rare “slot-machine grinding” on the other hand is extremely cumbersome and frustrating, and the addition of a mechanic that assists you to get what you want (like a enchanter that changes the affixes to desireable ones for a high, but fair, price of iron and componentes) is extremely welcome and would open for new build possibilities IMO.