Nice work! Congrats on getting it all working!
I don't think your nozzle is particularly large - most I've heard about are 0.4-0.6.
I'm assuming that distortion is caused by the layer start/end. If so,\ there might be some benefit in examining the start/stop timing.
Also, you could try a filled object - especially if you can use the new host software, which starts in the middle of the internal fill to minimize the start/stop effect.
Good luck!
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