I'm not sure how specific we can be but in the case of just covering the Baltic, would it be better for Germany to just build up through the Helgoland class and not bother with later stuff? Russian Dreadnoughts seemed structurally and operationally suspect, so at face value it seems perfectly adequate for the HSF to only build up through its Wing-Gun dreadnoughts and then use them and whatever Pre-Dreadnoughts weren't canceled by this 'smaller HSF' theory to protect the Baltic. Imperator Nikolai was the most modern dreadnought the Russians built during the war and it's barely competitive with the much older Helgoland class at least on paper. (We'll assume Nikolai and Mariya have a career in the Baltic instead of the Black Sea even though both classes were historically built to fight the Ottoman Navy.)
On paper the Gangut class is basically superior to any German dreadnought before Baden in a decent ranged battle. The belt armor was a bit thin, but Jutland suggests this wouldn’t actually have much mattered and said armor belt was very extensive. Meanwhile a dozen 12in guns on the broadside simply outmatches all the German 11in and 12in ships, all the more so because the Russian 12 inch gun was exceptionally powerful for its caliber.
Then again, if the HSF is being prepared to fight Russia instead of Britain, the whole spectrum of dreadnought design might change and historical designs we're familiar with might not get built?
They’d be somewhat different. If Germany built dreadnoughts purely in response to Russia starting to build dreadnoughts, the most extreme option I think plausible (no dreadnoughts… not bloody likely when even Spain got a couple), then I think we’d see a ship sort of like König but less refined and not so well protected as a result. We would not see Helgoland; Helgoland was built at a time when Russia had just had most of its fleet sunk by Japan. I calculated my numbers above on the basis of the Helgoland and Kaiser classes being constructed to ensure complete German Baltic superiority, and an ability to comfortably confront France if France were faced alone and avoid a close French blockade of Germany as occurred in 1870.
Actually, I think it would be wrong to look on dreadnoughts alone. After all, the Pre-dreadnoughts cost enormous sums as well and were in fact the reason British emnity started in the first place.
The thing is, until the Russian fleet wipes itself out against Japan, Germany plausibly needs a relatively large predreadnought force to control the Baltic. In 1904 Russia was planning a force of 16 modern predreadnoughts for its main Baltic-Far Eastern force, and pretty much had all the required hulls built or building. This is not a small number of battleships, even if its nothing like the RN which eventually had IIRC 41 x predreadnoughts. It was a godsend for Japan that the Tsar split the main fleet rather then waiting to dispatch a totally overwhelming force to Port Arthur as most Russian admirals wanted, but that’s its own tale.
You could shave a couple of predreadnoughts out of the German fleet anyway, but I was just trying to offer a bare minimal version of what could be cut from the HSF. In all reality, if Germany really wanted they could forgo almost all battleships and just trust in passage through neutral Swedish and Danish waters and wars being short (so stockpiles in Germany aren’t exhausted) as a means of ensuring an iron and steel supply. But it’s a bit optimistic to assume that will work; at least in a time prior to the understanding of the true effect that mine warfare submarines would have on the willingness of navies to conduct offensive operations employing heavy ships.
One could also trash the Siegfried class coastal defense ships, but that would be a pity as they do greatly amuse me. Literally designed to sit inside river mouths. Of course that also takes us all the way back to 1889; at that point money spent on more forts is still very useful, money spent on more field artillery or infantry is not as the weapons they carry will be obsolete by 1914. If you trashed all German battleships and cruisers and major naval facilities you could easily save 2.5 billion Goldmarks, and I bet a billion more goldmarks in operating costs. This is pretty unlikely though unless Bismarck become Kaiser.
I still haven’t gotten around to tracking down the numbers I know I have somewhere for costs of field troops.