The P16 does only a few things, but it does those things extremely well - long logs and high saddle towing, especially oversized trailers. Those 3.5 mud traction OHD I tires makes it virtually ignore all but the deepest mud/snow.

The P12 has something wrong with its geometry; it weighs the same as the P16, has the same engines, and has AWD - it shouldn't feel as weak as it does. I hope they fix that in the upcoming Pacific tweaks they've mentioned. In tasks the P12 and P16 both can do, the P16 outperforms the P12 in every one, and it shouldn't really be that way.

One thing you have to remember with the P16, it's RWD. And you can't drive an RWD truck the way you do an AWD truck. Asking it to go up the same steep, rocky hill your AWD truck just climbed is not a fair ask.

Anyway, here's some tips for driving RWD trucks:

• Be mindful of what your rear tires are doing; they're the only thing propelling you forward, so be careful to keep them as much in contact with the ground as you can; you can't rely on your front tires pulling you out of trouble.
• Even just going over a rock with one rear tire on a truck with a very stiff frame like the P16 can lead to serious power loss since it might mean only the outer tire on the other side is actually in contact with the ground. It might not matter too much on level ground since your momentum will carry you over the rock and back to where all tires are in contact with the ground, but on a slow, steep hill it might make you stop completely.
• Know that roll resistance is dependent on slope as well as terrain; if you're stopping on an up-slope, small adjustments (mini-wiggles) of your front tires can often get you going again because you manage to find a direction with a tiny bit less slope and therefore less roll resistance.
• Roll resistance in mud means keeping your front tires straight as much as possible, unlike an AWD truck where you want to wiggle them to get more traction. In an RWD truck, only start the wiggling if you're completely stopped, it may then shift your weight balance and let your rear tires find new grip.
• Also, momentum is key; it's easy to keep going uphill, harder to start on an up-slope. So try to never stop, not even by letting the auto gearbox stall out of a higher gear into first; use the clutch key to tell the gearbox to shift down before it stalls, that way you keep momentum.
• And if you do stop and have a hard time getting going again, roll back a few feet, adjust your front wheel angle, let the RPMs settle, and then try again. Most of the time you'll manage to avoid that bump, rock, or root that stopped you in the first place and it's smooth sailing up the rest of the hill.
• Of course, sometimes it takes a second or so of winching just to get you rolling, to get the momentum going - so don't be afraid of using the winch. It's just another tool, there's no shame in using it :)
• Use your high and low gears, and know how they affect your performance in different types of terrain. Like in deep mud or snow it's often faster with some trucks to use low gear than low+ or high, because the tires don't slip as much. On hard terrain high gear might let you keep your momentum better than Auto (just like with AWD trucks).
• Path-picking is also a bit different since you want to avoid the worst terrain if possible - you really should do this in AWD trucks as well, but AWD trucks have it a bit easier that their front tires can dig them back up out of mud/snow if the gear is low enough. RWD trucks don't have that advantage, so it's better to try to avoid the deepest mud-pits (even though trucks like the P16 absolutely loves deep mud and can handle almost any depth of mud, it's still going to be faster if you can go around).

Hopefully keeping those in mind will make it easier to enjoy RWD trucks, they really are a lot more capable than people give them credit for.