I have a lot of diagrams with shapes where I draw lines between certain points on the boundary of those shapes. With Tikz I can use nodes to draw shapes, and use anchors like "node.west" to draw lines to points at their boundary.
However, I find it annoying to always set empty brackets {} after the node, as I never have text. Also instead of always having to specify "minimum height" and "minimum width", I would rather have a "size" key with a default value. Last, I haven't found a nice way to define custom node shapes that doesn't involve low level PGF code which I know nothing about.
Up to now, I'm just using commands that draw the desired shapes at Tikz coordinates. But then I don't have the possibility to use anchors, which I would find quite neat.
Is there a Tikz equivalent of a node, which isn't designed for putting text, but just shapes? Or is there another solution that is similar to what I want?