My friend only has one kind of filament (ST-PLA) but I took a Stanley knife to it and removed a thin slice of material where the trigger meets the line release. This removed the layer line ripples and now it’s almost as slippery as Delrin.Maybe a more slippery plastic for the line release lever?
In general with 3D printing, if you have your extrusion parameters set correctly (e.g. not under extruding) and you run your temps as high as your filament and design will allow you, you actually have very good fusing of the layers - but because of the Michelin Man ripples on the surface it might not look very homogenous. But once you cut into the part, it should be very solid and smooth.
As for the temps, if you design your parts with minimal overhangs, then you can turn the temp up and the part cooling fan down - which will give you stronger parts.
When I first started this project, I spent weeks testing a particular filament to find the best settings and kept tuning them over time and while it is tedious work, you learn a lot.
For 3D printing peeps out there who are looking for more info on how to get the most strength out of your prints, there's a Youtube channel run by a young German engineer which has really great content and testing. The vast majority of 3D printing content on youtube is just about decorative stuff, but Stefan is all about structural issues. Well worth a visit - just ignore him trying to find his inner anchorman voice...;-)