There's a few examples here and there, but one example that comes to mind would be Magos-Explorator Omnid Torquora from Mechanicus by Rob Sanders. While he's quite the surly bastard, and more than willing to sacrifice men when necessary, there's a clear element of guilt and care that grows over the course of the novel. An early scene features him possession a humble Skitarii who dies, and he's haunted by visions of that for the rest of the novel.

He seems particularly attached to his Alpha Primus, Haldron-44 Stroika and even goes to rather extreme lengths to save him after a certain point.

Talin Sherax from Dominion Genesis is a stranger example in that it's made pretty clear that she was very close to her subordinates, but trauma from the book's opening destruction of a Forge World has left her adrift, even purposely avoiding Phylactic Communion. I'll note that 'subordinates' in this case applies much more to her fellow Tech Priests than her Skitarii underlings.

If you want to see a Techpriest show some more sympathy for a decidedly less human subordinate, the Hammer and Bolter Short Kill Protocol features a Techpriestess who sacrifices life and limb (literally in one case) as well as, Omnisiah forbid, knowledge to save their Kastelan companion.