14-16" is about the normal "max" most people achieve with a traditional drag link and track bar. Track bars are usually no problem because they pivot on the other axis (horizontal bolts), but drag links can get a bit finicky depending on how much misalignment your heims/TREs can handle. You have to get very deliberate about how much misalignment you're using in droop versus in compression, and at times have to Z-bend the drag link a bit to use more misalignment in bump, to give some extra leeway in droop.
The other thing that becomes a factor in many rigs (at least those where the crank pulley isn't behind the front axle), is front driveshaft length and max angle. If your front driveshaft is in the mid 30" range, and it can only travel ~32 degrees, you may be surprised how quickly you hit that limit in droop (especially depending on low vs high pinion, and pinion angle, and how high the tcase is clocked in the chassis). There are 40 degree+ shafts made in the aftermarket so it's not the end of the world, but might be an unpleasant surprise if you're trying to repurpose OEM components like many of us do.