i knew it wasn’t a boss drop because i found the ones i have from random sources. i generally don’t make a fuss about knowing where things come from, nor do i plan builds that rely on specific uniques unless i already have them. it’s just how i prefer to play… i try out lots of different builds and try to make them work with what i have at hand. and if i find a unique that’s useful for my current build, i use it, or if it’s one that fits a different build, i make a character that can use it.
as a long-time PoE player my concept of uniques may be different if you’re used to a system like D3 where the BiS for every item is a legendary. in LE, as in PoE, a lot of uniques are just useful for leveling (or barely useful at all), with a few that are more useful in the long term and a very select number that are actual BiS items for specific builds. with that in mind, i don’t worry too much about obtaining certain uniques, and i get a little thrill when i find something cool that i didn’t know about or i happen to know is a rare drop (exsanguinous, plaguebearer’s staff, etc). after 300 hours in the game i still don’t have a boneclamour barbute, which is a staple helm for a lot of builds because it’s generally very good. any time i look at a guide that suggests it, i just plan to use something else.
i don’t think the system is very intricate… it’s a little unintuitive for newer players that some uniques are on bases that can’t be gambled, i’ll grant you that. i think putting a database in the game that tells you where things drop is a bad idea. i like the sense of discovery of just finding things out for myself, and the sense of community of talking about things in chat or on the forum to share our discoveries. having things like a build planner and accurate DPS sheets in the game is great, and i’d love to see LE incorporate those to minimize reliance on 3rd party tools, but a database like you’re describing seems like it’s much better left to outside sources.