>> Your idea shows that SHIELD values Steve as an ASSET, not just as muscle. <<

If only. Phil does; SHIELD, not so much.

>> Sadly, I don't think enough of the individual agents were allowed to spend time with Steve while he was awake and could make at least tentative friendships. <<

I agree. He was deliberately isolated -- which is a tactic used in abuse and torture.

>> Right now, he's relying more on the visual cues: SHIELD uniform, likely to be trustworthy, US armed forces, likely to be trustworthy... what the HECK is she wearing, and why is her hair both fuscia and lemon yellow? <<

That makes sense.

>> None of those things make someone inherently more or less trustworthy, and because SHIELD hasn't really put any effort into helping Steve socialize (that we've seen), it implies to me at least that they really don't care if he settles in properly, just whether he'll follow the orders he's given. <<

Exactly. He's just a tool to most of them.

I don't like monolithic anything, so I've laid in some other bit characters at SHIELD who are more sympathetic and helpful. But in canon, it's rough.