A quick skim didn't turn up any more sourcing errors, but I don't have all the books so I couldn't confirm all of the spells even if I was studying them closely.
First, I'd make Hack affect be usable against the same creature multiple times on a failure, and on success still allow future uses against the same creature after 24 hours. If you must, increase the DC by 2 for each failure (resetting after 24 hours), but I don't see the mechanical need.
Next, Tactics can let you and allies treat the creature as flanked for the full minute duration with the initial effect (yes, even with ranged attacks; Dodgers will thank you), or increase the bonus to attack rolls for flanking by 2 if the target is already flanked. Flat-footed technically doesn't work for more than one turn anyways because it goes away when you take an action. Add an extra +2 to the attack roll for every tier of success above that.
Finally, add a second Hack that can be used at 1st level, both to ensure choices, and to give an alternative when flanking isn't viable (eg: Improved Uncanny Dodge, All-around Vision, etc.). No, I don't have any good ideas right now.