Horrible miniature junctions

[Solenoid]

I've got a game with extremely limited space for my junctions, I've done and redone them (often from scratch) to accommodate more traffic, but there's always the same problem which is trains blocking other trains. I cannot figure out how to do efficient junctions while keeping them small. Here are the main junctions I made, they're very inefficient, but somehow work (unless I get a gridlock, not very often fortunately).