Help me understand if mongoDB could be a good fit?

I've done my research on documentDB's, i still dont fully understand them but i want some help understand wether it could be worth my time to delve deeper into this. 

i run a game, and i'm looking at a reboot with some restructuring. 

The game uses a MySQL backend on the server side to store data

a shoretened schema is below

User

UserID

Username

DateCreate

Tank

TankID

UserID REF User.UserID

Rank

Awards

Map

MapID

MapName

MapFile

MapData

TankID REF Tank.TankID

MapID REF MAP.MapID

Color 

HoursPlayed

Equipment

I do a ton of single record writing..specifically to the MapData portion of the table. My understanding is that with DOcumentDB, single writes/reads are much faster than a mysql i/o. Very little BULK reading/writing, but there is some of that (5% maybe). 

Can someone help me understand if A) This is a good choice and b) how the layout in the document DB would look so that i can wrap my head around proper documentDB structures?

It's more important to understand how you are using the data to know if MongoDB is a good fit, than what the data is.

So, how are you querying this data?   Are you only inserting new data or also updating and deleting?

I'm inserting, updating and occasionally deleting. The server reads this data when the person joins into the game, and any changes such as rank, awards, kills, deaths all update the data in the MapData role.

My Website queries this data for logging in, and for generating top 25 players in the map/color/world.

Sounds like you can do all that pretty simply in MongoDB - the best
way to figure out what your documents should look like it to look at
your source code - you have some objects/entities - those are likely
to map directly to documents in the DB.