I think fleet reduction is something the germans will never accept, because they've learned how much Britain can hurt them with a blockade.
That depends; I previously posted about this on possible permutations of the WNT. Say...3-2-1 ratio in battleships, with the USA and Britain having 15, Japan and Germany 10, and all other Great Powers 5.
So let's say Germany keeps 8 battleships at home, and 2 in the Med. Assuming Austria-Hungary and Italy manage to afford (well, more Austria-Hungary) a full allotment of battleships, so they have 10 between them. Then there's the Ottomans, with a conservative strength of 2 battleships. That gives the CP 14 battleships in the Med. Britain needs at least to outnumber the Germans by half in the North Sea, so they can only send 3 battleships to the Med, plus say...a conservative strength of 2 battleships for France, leaving the Entente with only 5 battleships in the Med.
But that also leaves the Pacific defenseless, against 10 Japanese battleships, especially since the USA (and Canada) would still likely push for an end to the Anglo-Japanese Alliance. And with the alliance gone, Germany or Russia* will snap Japan up as an ally in Britain's place.
So yes, I daresay Germany is willing to accept a naval reduction, provided there are appropriate naval limits for Britain as well. They can always work around them, after all.
*Assuming Russia doesn't go Communist, of course. And that Germany snaps up China as an ally instead of Japan. IOTL, by the 1910s Japan and the Russian Empire had actually been cooperating on dividing East Asia into respective spheres of interest. The Treaty of Portsmouth provided them a foundation to work with, dividing Karafuto and Sahkalin along south-north lines between Japan and Russia respectively, as well as Manchuria along similar lines. Japan and Russia also agreed to split Mongolia between them, Inner Mongolia to Japan, and Outer Mongolia to Russia. And IOTL 1916, there was a secret agreement between Japan and Russia to work together in turning China into a shared sphere of interest, blocking further expansion of existing European spheres of interest in the region, and completely locking America out.
EDIT: In fact, as early as 1915, the Japanese already saw the alliance with Britain as not in their best interests, and were looking to Russia as a replacement. And Russia obliged, to the point of sending a Grand Duke George Mikhailovich in an official visit to Tokyo as a sign of goodwill and interest in Japan's proposal. Nicholas II also expressed support for the idea, and Foreign Minister Sazanov agreed, that Japan would make a useful ally in a region where Russia's limited logistics made for poor power projection. And on the Japanese side of things, the proposal had powerful backers in the form of Prince Aritomo Yamagato, and the Taisho Emperor (who personally welcomed Grand Duke George Mikhailovich on his arrival in Tokyo) himself.
The only reason the alliance fell through, was of course, the Bolshevik victory in the Russian Revolution.