Hello,
I have rebalanced version 0.5.5 for my play-trough. I guess my balancing is not really in line with your expectations, but I think it could be worthwhile to share it anyway

Maybe you get some ideas from it.
Basically the following changes were done:
- changed recipe times, power req., number of items,... (see attached spreadsheet)
- aligned the recipes such that I can build this tileable setup:

- factorio_oreprocessing.jpeg (451.08 KiB) Viewed 6445 times
Note: Each string can roughly keep 2 smelter of both ore types busy
- The ore washing plant produces stone as a side product
- the centrifuge uses lubricant instead of coal
- the matter compilator requires alien science packs but is ridiculous efficient (basically it generates roughly 94 ore for each alien artifact)
- I added an alternative path to create steel (1 coaldust from centrifuge combined with 4 crystallized iron dust in an assembler yields 1 steel dust which can be smelted into one steel bar --> ~25% more efficient but coal is needed)
So far for my taste if feels balanced and the efficiency gain make it worthwhile to use in a normal game
To made the changes affect my current game I had to enter this commands:
/c game.player.force.resettechnologies()
/c game.player.force.resetrecipes()
/c game.player.force.technologies["matter-compilation"].researched = false
/c game.player.force.technologies["matter-compilation"].researched = true
/c game.player.force.technologies["advanced-material-processing-4"].researched = false
/c game.player.force.technologies["advanced-material-processing-4"].researched = true
The same should work to switch back to the unmodified mod, but I strongly advise to test this out on a copied save!