I think most live players tend to push too much equity (betting strong hands/draws) when they barrel, compared to online where checking ranges are more balanced. The main adjustment is to fold more often already on the turn hands which struggle to improve on board textures which don't have tons of natural bluffs. River play depends a lot on players' tendencies after you already ranged your opponent on the turn.

1) Top pairs + straight blocker as a raise sometimes fold out better hands, get called by worse hands and in general they have more equity against the continuing range, as they're basically never drawing dead (unless villain has exactly the straight, which you block). It's not a pure bluff and it's an interesting exploit in single raise pots against villains that like to bet too many weak top pair hands.

2) Betting on those 3broadway straight boards IP, I don't like overbets, as there's simmetry in terms of straights, I think close to pot or pot is ok as a betsize, b66% doesn't make the OOP player very uncomfortable with a significant portion of their range. Anyway, it doesn't mean it's a wrong strategy.

3) Yes, you want to block their value betting range and unblock their bluffing range in general. Sometimes it's not possible, so you want to focus on just unblocking the main bluffs. Sometimes it's hard to find "natural bluffs", so also be aware of that when bluffcatching: if you can find these combos it doesn't mean your opponents will.