you need a block in the road somewhere right? otherwise the game is just a crafting simulator, something has to prevent crafting from being collecting 1 of each correct base then standing at your stash clicking the button till you have a full set of perfect gear.
im a new player here so give me 2 years with this crafting system and ill have a far more informed take than i do right now after a couple of days. but as i see it right now i really like this idea of forging potential being the stumbling block that prevents you from perfecting things.
im gonna compare to poe which also has immensely powerful crafting, its important to remember poe is a trade heavy game too so that also factors. what happens in poe is that you can infinitely tinker with an item, but you are limited by crafting material availability. the result in that game is that anyone can throw an alch on an item, but serious crafting feels very much like an exclusive club.
the vast majority of poe players feel like they get very little from serious endgame crafting, its a system where the materials to do it are very rare, very expensive but given enough of them ultimately limitless in power. so what happens is it becomes a playtoy of ultra elite players because if youre gonna waste currency crafting a thing it had better be the thing to end all things, its too expensive to craft a quite good item a lot of the time. then once you have that amazing item theres no point looting anything, its better to start with a white item and basically ignore dropped rare items if ur gonna craft.
by contrast here it feels like we have somewhat unlimited resources. i run out of a specific shard quite often but its just a case of add it to my filter and i can shatter some more within an hours play, if i needed glyphs or relics i can target them on the monolith system, its all there to play for. thats the opposite of poe where you might find 3 exalts in an hour one day and then go 100 hours without finding any more.
by the limiting factor being how much u can craft on the base the result is that you now care deeply about rare gear that drops, because you want something as close a possible to start from. so rather than the craft system invalidating the looting rare items side of the game, it strengthens it. then because you run out of potential and need another rare/exalted base to work on that further pushes looting these items and playing more, being excited about your rare/exalted drops.
what you get is that its easy and cheap to make half good items, quite good items, its accessible and it works in harmony with playing and looting already rolled gear. but you need to get rly lucky with ur hopes etc to push through and get really good gear while keeping perfect kind of impossible. it means you have a lot of iterative upgrades in endgame, you keep improving on your last item by a small margin. im not afraid to craft, im not afraid im wasting resources by tinkering with an item, by chancing my luck.
path of exiles orb system kind of does the opposite, it invalidates the looting game, it requires you to sort of play less and trade more in a way, its quite inaccessible to an average player and is inefficient at getting the average player their quite good next item upgrade… but it does churn out obscene perfect gear that shouldnt exist for the very elite players which forces ggg to constantly further restrict accessibility for the masses to keep that small percent of players in check. even for someone with many 1000s of exalts on hand and mirrors and all the nonsense you can be hesitant to attempt to tinker with items too much because the rabbit hole is endless, you can go forever till the item is perfect in theory but the cost is also infinite and you will regret ever starting. its a system with a lot of feels bad in there.
so i would worry about an ability to add potential back to an item. i think the system then becomes easier to make closer to perfect items and it pulls you away from the playing of the game that comes with ruining a base and needing to loot the next base to go again. theres a lot of benefits to having a system where you have this insane accessibility to an endless supply of crafting materials that are super powerful but then you keep the entire system in check with quite a tight bottle neck on an item by item basis via this forging potential. you dont feel bad for wasting materials on a failed project, youve just wasted the base, and you dont feel bad for wasting the base because it had to be attempted, at some point its limited forging potential had to be burned to see where the item ends up, nothing was lost in the attempt that should have been saved for a different project. i think forging potential and legendary potential are really the gatekeepers here that are maintaining the games item system integrity, its longevity, and relaxing those gates seems very dangerous.