The biggest frusteration for me right now is the terraforming and building system with its lack of refinement, poor expalantions and just lack of tools.
I draw allot of comparisions for building ships on here to something like Avorion, which is also a voxel like ship building game and the tools that has are amazing for ship designs that I would love to see incorperated in here. Some probably are not possible without making the voxel block be able to go smaller. I would also hope we may get voxels with elemental properties someday, to give us allot more flexability in the design of our ships, nothing like trying to go with a specific design and have to stick wings all over that dont go with it, or these giant box engines, its painful when other voxel like games seem to handle it allot better.