The Ottomans will be slower to get into the war, in OTL the bombardment of the Russian ports forced their hands before they were ready IMO. We may see a closer blockade of the Adriatic by secondary units of the RN, and even if not, more of the MN will be available, not being drawn off towards the Straits. Delaying or even stopping Ottoman entry into the war gives the largest benefit to Russia, it allows the deployment of more troops westwards. This is off the top of my head, so I've not looked at the numbers to see how significant that change will be.