Playing as Russia is easier than playing as Ottoman as you have an ally (Austrian) that can help to share some early heat from your enemies.
1) Golitsyn and others will take Iasi, then link up with the heavy arty and Wittgenstein's forces at Kishinev before heading down to Clujnapoca. You will need to help out your ally around Debrecen. Once you mop up, move down to Uskup before swinging east towards Plovdiv then Istanbul.
2) Wittgenstein's forces will have to cross the river then head for Kishinev, then Bucharest. Take care to avoid the coastal gun and large fortress. The final target will be Istanbul. Make sure you team up with your naval forces at Istanbul.
3) Sevastopol's force will take the long slow trip on land west towards Kishinev then down south to Burcharest then Sofia. Don't bother to waste $ on crossing the sea. Istanbul's navy outnumbers your navy 10 to your 6.
4) Add Kate to your battleship, team with Senyavin to isolate as many ships as possible then sink them by flanking. Move whatever ships that are heavily damaged to repair at your port near Sevastopol. The other port is too far away. Towards the very end, when your land forces take the factory and stable beside Istanbul, clear a path for your battleship to take up position south east of Istanbul for the flanking bonus.
5) Ignore all other Turkish forces with Dobrnjac. Do keep two ships to prevent them from crossing the sea to land at Sevastopol.
6) Save your progress constantly, complete this scenario before reloading an earlier saved game to conquer the yellow blinking port to unlock the bonus mission.
When I did it, it kind of felt like a conquest.