New Bars and/or risers question

My bike has a set of rental bars on it already, not sure what bend as the PO put them on. But when I am riding it almost feels like I want them closer to me so I can slide back on the seat more for hwy speeds to lighten up the front end to prevent that nasty speed wobble. Now when I am standing and riding I feel like I am constantly pulling up hard on the bars, almost like I am trying to lift them off the bike.

Now my question is before I decide what exactly i want to go with be it new bars and or just a rox riser kit, How far or how much lift can I go with the stock cables? I don't mind having to extend wires if need be but I really don't want to get my new stuff and then find out my clutch or throttle cable are too short.