The EE must have really screwed with the game balance, because OG BG1 is pretty difficult early on, and pretty difficult at the end, with "tank and spank" only being viable around level 4 or so, but not against boss encounters or the endgame.
And BG2 eventually starts showering you in +4/+5 equipment and more gold than you could imagine what to do with. It gets a bit easy at that point.
BG1 was HARD when it was released. Everyone used to cheese the final 1/4 of the game. EE and earlier Bioware patches made it a lot easier.
Gold rains from the sky in BGEE. Everything drops like 10x as much as it did in original release. The survival aspect disappeared and you no longer had to choose what you bought wisely. Magic items are ID'd instantly so you didn't have to guess if something was magic or not. I believe stuff in shops infinitely repop now and are no longer limited to 1 copy (or I may be misrembering this).
Also the standard difficulty of BGEE is different than it was in original. It's set for the player to take 30% less damage out of the box.
And I prefer low level DND, levels 1-8.
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