OKC made two moves that don't look flashy but made perfect sense for them (swapping Giddey for Caruso, then adding Hartenstein). That's a well built team that will continue to grow/improve and also, they still have tons of assets to potentially make more moves down the line if needed.
They feel like the true 2nd best team in the NBA currently behind Boston.
I think Hartenstein was a major add for them. Gives them additional size, rebounding, but also Hartenstein is a sneaky good passer and playmaker. Even though he's not a 3-point shooter, he can still stretch the floor a bit too and can be lethal that way. Now OKC could compete with the bigger teams as well (LAL, DEN, MIN).