What value does Investigation have for regular campaigns?


I have been interested in how to make the Inquisitive Rogue (Xanathar’s Guide to Everything, p. 45-46) valuable, but I’m having some difficulty wrapping my head around how to utilize some of its features.

Notably the Inquisitive Rogue gets two major abilities: The ability to “study” an enemy and always land sneak attacks, and the ability to use an Investigation check with a bonus action.

However, compared to other Rogue subclasses, this seems rather weak. Swashbuckler Rogues have a similar ability, to inflict sneak attack bonuses on enemies who are neither granting you advantage nor are near allies, and the Mastermind Rogues can use the Help action as a bonus action (making a major part of their playstyle).

But the “studying” effect seems rather weak, compared to the Swashbuckler Rogues’ abilities to taunt, gained initiative, and avoid Attacks of Opportunity.

And the Investigation as a bonus action ability seems hardly usable at all in combat (when a bonus action is most valuable), and seems pointless out of combat (when you usually can spend as much time as you need to investigating anyway).

Any advice as to how to use Investigation so that Inquisitives can get more value, without turning a 5e campaign into a detective show?