OK as an update, I can't do anything this major so it was a specialists job for me and the change from auto to manual is not an option I wanted to take, however I decided to have quite a bit done whilst they had it in the workshop and the same tech worked on throughout which I was happy with, so work done to resolve some issues were:
Oil leak, it was leaking badly and all signs were the rear main seal, sump gasket and possibly the front seal, so bit the bullet and they had the 330i for 2 days.
Result was it wasn't the rear main seal, the issue was sump gasket and oil filter housing gasket. So it all came apart, and as they had access to much more we went further, anything looking like it was perishing got replaced, I'd already done the DISA,so we had new lower control arms fitted with new bushes, 4 wheel alignment done, new gaskets and bushes where ever needed at the same time as well as a full service, coolant change and brake fluid change.
We've had the car since new and my parents drive it these days, its just clocked up 100k and up until 4 years ago had BMW service/mot etc on a regular basis, but due to one thing or another (mileage related) we slowed down on the maintenance side and just did things that were felt were needed however when I drove it in November it became obvious it wasn't as sharp as before, well now its as good as it was when we first had it, it feels solid, plenty of grunt, smooth to drive, instant performance, brakes are sharp, handling is superb and no more tramlining or off camber moments, and all the parts that came off were the original parts fitted in 2003! And to recall, I replaced the battery in Sept, the one that came out was the original battery as well, so I think these are doing well.
So we have a plan, interior next, its clean and relatively unworn just suffering from age so thats next up, and its showing signs of minimal rust to the n/s front wing on the arch so again that needs replacing. Then, who knows, maybe get the wheels refurbished (they've never been done but are in excellent condition).
A little misting on a rear damper so we'll plan on having those done. But all in for a 17+ year old car, its bloody brilliant. I see the work done as a safeguard for the next 17 years.