1999 GR 2.8 Turbodiesel - need overhaul??

Hi guys, just bought a 1999 GR 2.8 Turbodiesel, 255000km. Great car, but since I'm new to Patrols I don't really know what to expect.

I have a couple of question marks regarding the engine. It runs smoothly and my issues are minor, but if necessary I would be happy to spend a few bucks getting it ship-shape.

1: Starting in the cold - it starts ok but it seems a few of the cylinders aren't starting right away. When I crank it, it fires but I have to crank it for a second or two AFTER that or else it dies.

When it starts, it runs a bit rough for just a second or two (literally) - then it runs smoothly.

2: It puffs out quite a bit of white smoke when i starts, especially in the cold. Nothing drastic but a bit more than I'm used to.

When it runs, no excess smoke or white smoke, just some black smoke when topping out the revs at full throttle.

3: "Smelly" exhaust - especially when idling, also when up to normal temperature - the exhaust smells like it's "rich" in diesel, if you know what I mean. Nothing major, but more than I would expect.

4: Noisy turbo - the turbo-whine is quite noticable inside the car when powering on. Again, nothing major but more than I would expect.

5: From time to time a few very minor "flat spots" in the power - don't know how to explain it but sometimes, especially at low to medium power, the power fluctuates a little bit, almost like a small "stutter"...

So, any thoughts if my new car would benefit from an engine overhaul? What would be the suggested points to check out? If any.