Yes the game has it's bugs and glitches. But they have implemented a monthly update system that focusses on fixing issues as well as when due releasing new content. Unfortunately these updates and developments are only focused on the Multiplayer. Singleplayer has no more attention form the dev team, which is logical for a game that has passed it's 1 year birthmark.
To your final question: the turning tides DLC will deliver 2 new maps in December 2017 and 2 more new maps in January 2018:
AVAILABLE IN DECEMBER:
- New Map: Cape Helles
- New Map: Achi Baba
- New Operation: Gallipoli
- New Elite Class: The Infiltrator
- New Vehicle: L-Class Destroyer
- New Vehicle: C-Class Airship
- 6 new guns and 3 new melee weapons
- New Specializations, Service Assignments, and Unlocks
AVAILABLE IN JANUARY:
- New Map: Heligoland Bight
- New Map: Zeebrugge
- New Faction: British Empire: Royal Marines
https://www.battlefield.com/en-gb/games/battlefield-1/turning-tides?setLocale=en-gb