I'm currently playing as a ranged Fighter who is from the RP more a wild ranger type, not a heavy armored soldier. From the background the use of bows would be more appropiate than of crossbows which have a technical "civilized" vibe.
However, what is the advantage of a longbow compared to a heavy crossbow? I'm not am min-maxer but my char already has to suffer from some RP restrictions, so my main weapon should be the best option. Crossbows in BG 3 seemingly are not restricted to one use per turn as in normal DnD. A crossbow is 1d10, a longbow 1d8. Why should I use a longbow?