I call for zero flap at 400 feet AAL. Once it's away, I'll do me scans and engage the a/p before calling for after take-off checks. I find this spreads the workload very nicely, allowing me time to ascertain how much other traffic I need to thread me way thru.
If I'm feeling brave (only when there's little or no other traffic to contend with), I'll leave the a/p out to 10,000 feet.
For the descent, I usually take the a/p out at TOPD if the arrival is particularly awkward. But, if there's a lot of other traffic around, I'll leave it in because, no matter how awkward the arrival is, there'll be too many other aircraft blocking my descent. If I haven't disengaged it any sooner, I'll do so at the IAF or, if using a visual approach and a circuit, I'll disengage the a/p before manoeuvring to join the circuit.
A Kingair is pretty flexible tho and other circumstances can dictate the need for a different set of strategies...