I've tried thinner wire but this is not suitable running locos from the overhead system, they bent upwards. regarding the thickness of the wires, mine are 0.7mm and theya re strong enough to be suitable for pantographs to be used against it.

I have always found ways to a.) simplify the design, make it less bulky and my latest idea comes with 3 wires being soldered together and soldered onto the support bracket instead of having to bent the wire at the end which than looks bulky because you have 2 loops at the support bracket, this way you just have a soldering spot which is hardly noticeable. the other improvement is using Sommerfeldt wires from the shelf makes it more bulky, the ends are bent back into a loop plus the upright supports are more or less together which you don't find on a prototype catenary system.

I may look again by using 0.5mm wires when I got the new garage extension up and trains running to its full capacity and use proper tension methods.

John