Black Mesa: They Hunger would honestly be such an amazing remake of the classic custom Half-Life 1 GoldSource (GoldSRC) Valve fan-game and mod They Hunger in the Source Engine, but with all the definitive and descriptive visual/graphical, textual, auditory, and kinesthetic aesthetic formatting and styles or themes and elements of Black Mesa.
Now I think if HECU and Black Ops worked *along* with Black Mesa Security Force they could have contained the invasion sooner and Combine would have never stepped in.
Honestly with how Black Masa is I wouldn't be shocked if they somehow in a different timeline instead of the whole bullshit that happened in the main timeline they instead cause a Zombie Apocalypse through some Virus they made that somehow got out which would be worse then a bunch of Headcrab's cause Virus