Add a corresponding non-power bonus to the consoles
Basically this. If you look at all the things making high power levels across the board possible, they are all attached to items or procs that have additional benefit or use. If these items were just flat +power like the consoles, they probably wouldn't be as desirable. Leech for instance, doesn't just increase power, it also has the potential to strip power. MACO shields... it's on a decent shield. I mean, I guess if you had a console that gave an absurd amount of power, it might be valuable to certain classes/builds. Or maybe consoles that raised multiple power levels would carry more interest. With the abundance of multi-functional and/or universal consoles available, hardly anyone is going to slot a console that only augments one thing unless it's flat damage of flat defense of some kind (i.e. shields/armor). A couple points of power just isn't good enough to compete with the other options. Set bonuses for consoles could also be an answer as well.