This does not appear in the compendium; apologies if it's already been denied.
As I was documenting cable behaviour this evening, I noted:
1. How iron cable can handle both HV and EV
2. How glass fibre cable breaks the linear progression of cable efficiency.
3. The shortness of the progression.
I suspect at the moment that few people bother transforming power to EV since glass fibre is just too cheap and convenient and serves most purposes. As such, I'd like to suggest a rejig and expansion of cables. I'm refining the idea and typing at the same time so consider this a first draft and open to discussion and further refinement 
1. I suggest consistent naming of the cables based on the voltage for which they are rated.
2. I suggest an expansion of the cable range to separate EV from Iron.
- VLV Cable - Made from Tin, no changes other than name.
- LV Cable - Made from Copper, no changes other than name.
- MV Cable - Made from Gold, no changes other than name.
- HV Cable - Made from Refined Iron, handles up to 512 EU packets.
- EV Cable - Made from Advanced Alloy, handles up to 2048 EU packets.
Wrap 1-3 layers of rubber around them to insulate as normal.
3. I suggest a serious nerf on glass fibre cable. In the real world, it's signal wire and not (yet!) capable of carrying power effectively. However it IS virtually lossless. I suggest reducing the voltage rating of glass fibre to 32 EU packets but leaving the 40 block range (or even increasing it). To compensate, perhaps increase the yield from crafting from 4/6 to 10/15. This should suffice for the majority of wiring in people's workshops and bunkers for those that care to burn a few diamonds in exchange for not having to place batboxes all over the place.
4. New cable - AHV Advanced High Voltage cable that has a lower voltage drop than HV. Crafted by adding carbon mesh to rubber then wrapping it around RefIron.
5. New cable - AEV Advanced Extreme Voltage Cable which would behave like current glass fibre (40 block / lossless) but handle EV. Crafting should be suitably complex like making insulation from carbon mesh and advalloy and wrapping it around a regular glass fibre. I also suggest that this cable NOT be able to make bends. Not sure if it's possible to prevent cables from connecting on a side but Buildcraft does it so hopefully it can here too.
6. The AEV cable is of course PLASMA so needs a very HAYO new transformer that converts EV to Plasma. Naturally this is an Advanced Machine.
7. Potentially some rejigging of the voltage drop rates across the board so as to give consistency and encourage people to use the higher tier cables.
Right, bed time. Looking forward to your critiques!