If there was no preferred join, I'd definitely go for a base join in this case - keeps you out of the way of the parachutes, but also gives you plenty of time to observe the traffic in the circuit, and the flexibility to fit in with that traffic, which the straight-in doesn't.
Keef, you are correct, the 45-degree join is not legal. As far as I'm aware, it's not legal in the US either, but everyone seems to ignore that
However, that aside, the easiest way to do a 45-degree join from this direction would be to fly overhead the airfield above circuit height, then fly outbound, descend to circuit height while making a 180-degree turn onto the 45. That would defeat the object a little bit, since you'd be flying directly overhead the airfield, presumably where the parachutes are dropping, which is what you're trying to avoid to start with! The other alternative would be to remain well to the east of the field, outside of the ATZ and well outside the circuit, and then turn onto the 45... but this takes you several miles from the field, at fairly low level, and might be tricky to navigate if you're not familiar with the area, depending on how easy the field is to see. I think I still prefer the base join.
FFF
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Edit to say to Kingy - yes, you're right, A/G can't give you instructions. But there's no harm asking them what they'd prefer, and then following their "advice" once you're sure it's safe to do so.