I think it would be helpful if the player's current progress with all known engineers was written out in one of the "startup" events. This would make it a lot easier to give the player information about what mods and effects that can go after.
For example, in the app i'm working on, I list all of the modifications a player can perform, and allow them to select a modification as a "to do" task. The task has some details about what engineers can perform the mod, but I can't let the player know in the UI if they actually have access to the engineer or not. It would be helpful if I could so the player would know who they need to go unlock to perform the engineering tasks they want.
For example, in the app i'm working on, I list all of the modifications a player can perform, and allow them to select a modification as a "to do" task. The task has some details about what engineers can perform the mod, but I can't let the player know in the UI if they actually have access to the engineer or not. It would be helpful if I could so the player would know who they need to go unlock to perform the engineering tasks they want.