a standard lift kit will not do much for your articulation, for real gains you have to start adjusting shock lengths and mounts, add disclocation cones softer springs, but for real flex on road handleing will be comprimised, i take it your anti roll bars are still attached, the first way to increase articulation is remove them. this will reduce the amount of resistance the suspention has against it allowing it to flex more freely but the BIGGEST thing that will improve offroad capability is the numpty behind the wheel. an experienced trial driver/ challenge driver could destroy a newbie with all the kit in the world with a standard machine and then secondly most important is tyres, height and grip level will get you far
hope this gives you an idea