I've got 48 coke ovens and I could easily build more as I never have enough charcoal surplus to be happy. 99% of my charcoal turns into alumentum though which is then burned across dozens of alchemical furnaces for automated alchemy (alumentum production itself, nether quartz and certus quarts doubling, metal doubling, steel production, clay transmutation, etc, and also crystalizing essentia). I also burn a little alumentum when my steam tank is running low in the unlikely event that demand is higher than the 2 36LP RC boilers can pump out off of creosote.
The only real issue with Thaumcraft creation of charcoal is finding a reliable source of ignis that doesn't involve burning off charcoal to get it. You can use gunpowder from a mob farm, if you've got one. You can make a snow golem farm and then centrifuge the snow. Any other source of ignis is just not as renewable and reliable as it is when you get it from charcoal directly.
The only thing my steam production is really providing direct power to anymore is a bank of LV centrifuges, ore washers, thermal centrifuges, and packagers. Everything else in my base runs off magical energy or diesel (soon to be biogas now that I built a distillation tower last night).
As I move towards and through EV though biogas won't even be a great option anymore as it requires 4 or more HV turbines to keep a EV battery buffer or MFSU happy full time. At that point I need to build out infrastructure to supply my tungstensteel boiler with 24/7 alumentum access and build a GT steam turbine.
Although, maybe I could just build a GT gas turbine instead and run it off biofuel with an EV or even IV dynamo?
I really wish I understood IC2 reactors better. I did manage to get a 0 chamber reactor working properly in SSP without making a crater. But that's like 32EU/t, if that. I built a MOX reactor in SSP also but the HU % just kept going up and up and it never stabilized to a point where I thought it wasn't going to explode. I guess I just really don't get the nuclear stuff yet. It's something I've never messed with and frankly it scares me a bit. Obviously it's possible to contain any mistakes, but it's just not something I really want to experiment with in my base as it's an unknown quantity. I suppose I'll need to mess with it eventually though because I need to get to a point where I can sustain an AE2 network with autocrafting realistically before I can move on to Fusion. I guess I could also look at Naquadah, but that's really a PITA unless, and even if, you go with bees.
I guess if you're comfortable with nukes and mox and liquid reactors and the like it's much easier to transition off of steam and charcoal early in the progression, even as early as the MV stage. I mean even taking a few dozen RTG (sp?) reactors and pointing them at MV battery buffer or MFE is viable at that stage if you've found the right ore veins. If you're unfamiliar with reactors and just plain scared by a higher likelihood of explosions than GT machines in rain, then steam is a thing.