Creating a reference database

I have a reference database that I use in chessbase / Scid when exploring openings. It's largely made up of games by strong human players. But if I'm researching an offbeat opening, I sometimes create an engine tournament to create games and to give ideas about lines to explore.

Do people tend to create their reference databases using high rated human games or do people tend to exclusively use high rated computer games on the basis they will be less likely to have blunders that skew the stats?

This is just my own opinion!
I think that people are learning more and more to work in conjunction with computers. Computers will play the 'absolute' best move, the issue with this is there may be other alternatives which allow for your opponent to make more human mistakes. For this reason given your rating on Lichess ( you may be higher in person) I think focusing on other high rated human games is your best bet. You and your opponent cannot play endless computer moves, looking at the human moves would be your best option.

Thanks. I wonder if a hybrid database is the answer