You are talking about fiendlock, which is only one flavor of warlock. And Wyll is the best example how a character can end up in a pact without planning too.
If you are a GOOlock, you might not have made the pact knowingly - you might have read an eldritch book, or had an encounter with a strange being - GOOlock is actually the subclass, that makes the most sense in BG3, especially as Durge, since you were in very close proximity to an eldtrich being for a while and it looked for allies:
The Elder Brain under Moonrise
Feylock can be a good thing too, there are a lot of well meaning patrons. My bard/feylock in our current DnD game has one of the Sea Lords as patrons and they are guarding water creatures and environments. My character made the pact after saving a n innocent sea creature and Elias, one of the Sea Lords, approached her and offered her power, if she looks out for sea creatures and keeps them save. Her father is a ranger, so she felt that this is a noble cause and would have done it anyways. Not every fey is a hag or other mean spirited creature.
There are more patrons in DnD, some of them very likely evil others good, but warlock doesn't have to be a bad thing.
And since it is your game, you can even flavor your fiend patron as someone like Crowley (from Good Omens, not Supernatural in this case), who just doesn't want to meddle in hell politics and is looking to settle down in Faerun, maybe needing a mortal to show them the ropes.
Edit: And warlocks can do a lot of stuff, since they get their spells back on short rest. the pacts are also pretty good and make for different playstyles.
