Nice post. These hands are a nightmare.
Flop: Yea, it’s a little too passive to check-call with your hand (I like check-raise here). You really want to know where you’re at. Some exceptions are when you know his opening range pre, c-bet %, and/or double barrel %, which would allow you to either pot control or trap on later streets.
Turn: He’s polarizing his range given the board, so holding either a mid-to-high pocket pair or AK/AQ/AJ/A10 (likely with spades). Don’t worry about a fourth 7. Again, a check-raise would have told you a lot, but certainly can’t fold.
River: I think you had to check, but his bet is wild. Further polarized range... now he either has the goods (AA, AK, KK) or a
bluff (mid pocket pair or flush). This is actually a very good bet on his part if he knows what you’re holding, but for you it comes down to what you know about him...
Has he ever bluffed off his
chips? Usually you spot these players right away. If so, easy call.
Is he a tighter player? If so, easy fold.
Do you know nothing about him? Ok, then rely on math and his betting. Math is close to even money I think (not gonna run the numbers). With regard to his betting, his bet sizing and position
tells me he WANTED you to call all along, which makes me think AA/KK, mayybe AK. I fold.