These levels are a much higher quality compared to your older ones!
The goal, teleporter, and switch entities don't fit the texture. Usually the average texture size for these (and arrows too) are 128x128. The teleporter and switch radius size are 0.5 to fit the 128x128. And for the goal it's 0.75.
There are also some texture clipping in you levels too. You can shift+left click a face of a lump to change the texture of only that face of the lump you selected. You can also select a lump or a face and press S to align or fit the texture. Pressing "fit" helps a lot.
One last thing is that coins are usually placed one block above the lump it is on. (on the 8 grid).
Hope this helps and can't wait to see more levels.