This is actually my biggest complaint about the game. I have little nitpicks here and there but I really hate the power line system, but only when we're talking about INSIDE of a factory. I'm totally cool with the poles and lines for outdoor stuff, or for connecting your generators to your factory buildings. I hate it from both a logistics and aesthetics perspective. I have a two ideas for a solution but I'm not sure how good they are.
First idea is powered foundation tiles. Make these a tier item so you have to unlock them, but once you do there is a special foundation tile that can be connected to your power grid. This tile then connects to more of the same tiles that transport the power through them. Anything built on the transport tiles automatically connects to the grid. Kind of defeats the number of connections mechanic is the biggest issue I see. Aesthetically, these tiles would have like a mesh cross in them with conduits running beneath. Think the lines on a circuit board, but in big black/grey wrapped conduit lines instead of bare gold, and that is covered by a see through mesh you can walk on safely.
Second idea is similar to the first, but this would require them to introduce roof foundation tiles. Same basic idea, but this time you build a roof tile that has a hanging power pole from it (the pole should be short for clearance reasons). You connect your grid line to this pole. The tile then has suspended cables hanging from it with very low clearance (like 1 meter or less) in either 1, 2, 3, or 4 way orientations (kind of like the player walkways). You build these "line tiles" in the roof above your current floor sending the lines where needed, then when you need to you can drop another hanging pole tile, and then connect your buildings to that. So you still have lines to your buildings everywhere, but they are up high and the connections to the buildings and the tiles are vertical so less clipping issues and less "well that looks unsafe" kind of thing. This also preserves the 4 connections per power pole limitation.