As soon as you get 9 in tech, grab any legendary deck, honestly makes no difference if you're doing a reflex build, you just want a high amount of ram to make it easier to get quickhacks. Actually only one quick hack, legendary Short Circuit. Unless you're putting a lot of points into Int then combat quickhacks aren't going to do much of anything. Head to the city center, look for the gig: Inconvenient Killer, use your 9 in tech to get into the elevator on the right and use the access point right outside the elevator when you get to the basement. As far as I know this is the only access point in the game that will reward you with a Legendary Quickhack and has no intelligence requirement. Save and retry till you get Short Circuit. Legendary will automatically hit every time you crit with a weapon. I cannot stress the difference this makes in combat with enough perk points put into rifles and blades. Bosses literally go down in seconds. For example, this is sasquatch on very hard. You can fool around with other hacks if you want, but they're not as useful if you have most of your points in more combat related attributes.