sorry if someone already mentioned same things, there are just too many comments above. sorry for long text
it seems devs focused on "progression" than "outcome". in fact the change about tech in SE-- is also about progression changes. outcome of game is same but not progression, the path to achieve those achievements (tech, new entities etc). we do not know much yet so just a guess and observation from what we saw in previous FFFs
what I mean. imagine there is a mod which gives legendary items already. there are tens, maybe hundreds of mods like that actually, "there is a mod for that". the progression to achieve them is different though, just expensive recipes, different items in process etc. now in this design items are same with vanilla (no new objects) but different quality types of them. from point of inventory handling, sorting, it is not that different from completely separate items other mods offer. if I remember correctly in reddit one of the devs said the different quality items would not stack, so every item and their different qualities could be considered different item with different stats. if you put a different icon and attach a recipe to it, then congrats, you made a mod, just like others. the change is just the progress for achieving them. outcome is same with mods.
consider this: every item you generate is legendary (top quality). then where is the challenge of game? is the challenge of automation changed? no, it is exact same challenge, just numbers are different. check your favorite site or tool/mod to get new numbers and continue design from there.
so it comes to the first thing I said. progression of achieving those MK2/MK3... versions are different. that is the new challenge. take it, or not, up to player, optional.
from comments I see people dislike the idea of that "random progression" to achieve those, but that is my observation only. if it was a fixed/consistent way of achieving those then it would not raise those concerns. but then how different would it be from another mod?
my personal opinion and expectations about this FFF stuff: endgame "new" content is nonexistent to be honest, because "there is a mod for that". if you want to limit yourself with subpar items then sure (use vanilla, base quality), but there is always a higher quality item you can get (legendary stuff). what happens when you achieved them? done, nothing more to do. your factory most probably will work in the same way as before, just different numbers. so you did not invent something new actually. for endgame now every player has to design two factories probably, one with default quality (starter) and one with legendary quality (later). of course everyone would go for top high quality one if they could, because why not? "progress" is the new content, or automation of winning over RNG is new content. sorry, not exciting or funny at all. if I need 5 legendary item and within 10 seconds I created 5 then challenge is over. it is RNG after all, unlikely but potential, also 10 hours with no good result too, just depends on RNG, not your super fancy design.
not sure if devs count responses in a category but I am on the negative side if it matters, unfortunately. I understand what devs tried but I just do not like the implementation, because outcome is not different than mods and progression is not good I would say, does not fit Factorio style challenges. putting quality items in game, even tied with a checkbox does not make it optional in my mind. pollution and biters are optional too but you take them as game's challenge always and game has to balance around these too. just disabling one or two might affect gameplay a lot (biters especially, or expansion of biters for example, peaceful mode). this new quality feature would not affect much for sure but then for endgame it would force player to build multiple factories. anyone who dislikes that new "random progression" challenge will hate it.
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to be honest if someone asked me how to solve that problem what devs tried to achieve, at first I would probably do the same thing actually (use RNG). introducing a new item/resource is too lazy and devs tried to avoid it for obvious reasons (because there is a mod for that). but also I feel this is lazy
I would go with the "outcome" path perhaps. just a fluffy idea. I would instead implement a new beacon which accepts some limited number of modules (maybe one). then invent a new kind of wire which can connect from that special beacon to every entity within range, not like a power wire. lets say the module you put into beacon is legendary module, so it shall make every entity within range legendary quality but only if connected with that wire (even though item built is base, regular inserter or assembler or other stuff). then that special unseen wiring from beacon to entities would be needed to set manually (or blueprint). of course beacon has to have limited connections accepted to make it more challenging. so for example if beacon supports four connection, then within area it should be able to support total of only 4 items (2 inserter plus 2 assembler = 4 , or 3 inserter plus 1 assembler). of course it is a beacon so you cannot fill it within our beacon rules, limited range and space etc. in that case the designs would need to change a lot, and quality modules you put would allow countless options, and you can upgrade them when you unlock new modules, then connect to different entities perhaps. it would also push people to use beacons more (because most people hates them). also items are always same, their stats would be different depending on that special wire so no inventory hell. I do not think it would be a super good idea but probably I would go into this kind of "design" related challenge instead. making new and complex factory designs is better and more fun than RNG progression I would say. the solution I provided is absolute and consistent, not RNG based. probably it is hitting the same roof perhaps but it is just an idea anyway. the progression is not the challenge though, outcome is different because of new design and it can vary a lot depending on how the structures are set by player, which entity takes quality bonus and priorities, effects etc. in the devs' solution when you access the highest tier then there is almost no potential upgrade. in this solution it is similar but progression is more factorio progression like, you build more, make factory efficient and upgrade more to open more options, at least predictable and consistent.
this kind of solution could also be applied to our current beacons, so we could avoid the boxed 4x4 like beacon structures. definitely changing a lot but could help about boring same repeated designs. beacons within spagetti factory would really look nice.
why such a solution? lets be clear, most people shall ignore legendary radar, or pole, or maybe turrets even. what does a legendary gear do? do we really need that? actually no, we need legendary entities, not intermediate stuff. it does not affect production, then it is not so fancy and does not have that "I must have this" feeling. anything that affects production is good, rest is meh.
