I've had that issue before and what helped me was this: I start with creating a group and then in the end pick the members of the group that have developed to be the most vibrant. So I can still start with the history, but don't end up with people who aren't much *more* than their history.

This obviously doesn't work for hardcore loners, but for OCs in groups (friend groups, family groups, work groups...) it's worked quite well for me. Essentially, since there is a group of people that I develop at once, I don't just develop their history but also their relationships, their opinions on one another, their dynamics, their strengths and weaknesses as something that is balanced out by or clashes with other members of the group. Their personalities grow because they need to be different from each other, and so on. And all of that happens fairly organically while the history is developed.

And then it tends to happen naturally that some members of the group are more colourful and vibrant and call out to me more to pick them up as individuals to play in DWRP. Sometimes only one, sometimes two or more. The advantage is that there's a fleshed out background (and the disadvantage is that I keep wanting to talk about those other character, but that's where self restraint comes in).