I designed a part which the toolmaker struggled with for many months.

It's a thin walled bucket, about 420mm in height.
Wall thickness is 2.5mm but the base (where the gate is) was increased to 3mm.
Part weight 1.3kg.

Material is clear Polycarbonate.

On the trials in China where tool was made, gate was originally about 3mm diameter, but then we changed it to a 6mm valve gate. The machines in China managed to produce parts like this at reasonable temps, but here in Australia we are struggling, and needing temps of around 330/340 and core temp of 90 deg C. This is on a 1200tonne machine

This is with a PC with an MFI of 36.
We tried CD/optical grade PC with a MFI of 70 but had issues with it cracking before ejection (likely moisture related)

I have inspected polycarbonate containers of similar dimensions, (Cambro brand), and they have gates of approx 8-8.5mm.

Personally I think the most obvious thing to help here would be to change valve gate to 9mm.
This more than doubles gate surface area, and halves shear rates. I'm getting mixed opinions on whether there will be any improvement.
From my understanding, even if the thin wall and the distance needed to travel is the issue, increasing the gate size will surely help to some degree.

I tried modelling the flow with Autodesk moldflow however couldn't seem to change the gate from auto to manual in order to investigate.

Any thoughts on this?