Low speed torque and driveability ?

Drivability. HMMM. Yes, well that is a keg of worms discussion and involves a number of topics.
Idle quality to many people is the first to come to mind. Generally a fairly smooth idle is desired and is partly the trend to wide LSA's on modern engines. This is compounded by the high port flows found in these engines. Then there are many tha find a bit of lope to the idle acceptable, while a top fuel idle is not street friendly. This all comes down to intended end use, driving to church or for groceries, towing a trailer, weekend track days or an all in race car.
Will the car or truck pull away from a stop smoothly without fuss and bother?
Required rear gearing and converter stall RPM. If a manual trans, do you need to apply throttle just to get the clutch engaged. I am referring to more throttle than a factory combination. These all relate to driveability. A high stall and a low final drive are great for rapid acceleration but get real tiring on the highway. Not only that but fuel economy. There is a local fellow with a poked and stroked and built Big Block Buick that can not make 200km which is 120 miles on a full tank of 91 gasoline. Like a Saturn 5 that liftoff kick in the backside is thrilling but the cost to play is expensive. Listening to the engine ticking over at 4,000RPM at 65 to 70 MPH wears thin quickly.
How much tinkering has to go into keeping the engine running properly is part of driveability. The more power per cube built into the engine, the more high strung they become. Atmospheric changes tend to affect it more than the OEM offerings, dictating tinkering.