To drive the car hard with cold engine temp is not the best idea, I say be patient so the engine life to be longer.

On to the punchy (torque) issue, the 3.6 mkI engine is not known for its jumpy nature. It is a smooth engine with good power but due to the engine capacity, heavy stock flywheel, engine mapping the car doesn't feel so powerful/jumpy. There are a few options to take care of it:

-ECU remap
-LWFW
-High flow exhaust

It's all up to you, but you won't get your money back

 

Oil temp should be at least 200F.

 

I don't have anything to add regarding the punchiness off the blocks, I think people have covered it well.
It did catch my eye that you feel the car needs warm up to be responsive. My car is a C2S, so not apples to apples, but I have never felt the car to hesitate when cold. It is ready to go, I need to behave myself not to push it too much before oil warms. I do live in CA, so not sure if you are experiencing much colder starts.
Anyhow, when I hear less than responsive on start up, that feels like an issue.