By the nature of blueprints, or any other node-based system, you sometimes end up with connections running in ways that make it tough to trace visually. There’s no avoiding this, but one thing that can help is the use of reroute nodes. They are simply pins that you can add in the middle of the connection line, and they allow you to move that line around to keep it from overlapping other nodes, etc. Basically just clean it up visually so that the connections remain clear at a glance. You can also branch off of reroute nodes as you would any other pin that allows it. In a sense, you get to ‘bundle’ your lines and keep them neater and less visually cluttered.
Here’s a video of how it’s implemented in blender, as you can see it can be pretty handy for keeping the visual ‘flow’ of nodes under control, which is directly related to how complex you can get with nodes and still understand what’s going on.
I think this would actually go a really long way towards keeping the data flow in more complex blueprints clean.