I re-examined what I was doing, and I did get the Machine Controller cover to work on the Large Steel Boiler. I could have sworn I tried this before, but I think perhaps I'd only tried it on the input bus, not on the controller block. User error, basically.
I'm not thrilled with steam, largely because the piping expense of moving the steam to the turbines is getting high. Steam's energy density is very low compared to the liquid fuels, so it needs big pipes.
The main reason I'm focused on steam is that the trees are a continuing, renewable resource. I've been meaning to put together an Oilsand -> Nitro Diesel line for a while now, but that means periodic mining expeditions just for fuel. Probably a lot of energy per mining run, I'm still a little wary.
I've got a biomass -> ethanol setup, but it stalls because the source of biomass is fermented saplings from the tree multi-farm, and the output chest fills up with wood which halts sapling collection. I guess I could go wheat multifarm -> plantball -> biomass -> ethanol. Most foods don't return enough energy to break even, but plantballs give a decent surplus.
I've done some experimentation in the creative testbed world, and my impression is that methane isn't worth it. LPG is a decent gas turbine fuel, but I won't have any good sources for that until I start oil drilling and getting Natural Gas or Light Oil results. Right now Oilsand's my only petroleum source, and Oil -> Nitro Diesel produces 4x as much EU as Oil -> LPG.