In order to stand out as a gaming blog you NEED to vary your content. This allows you to capture a wider audience therefore increasing viewership. Here's some ideas...
This one is self-explanatory; you personally play a game for at least 8-10 hours or enough to develop a solid all-encompassing opinion. This idea for a gaming blog is magnificent and can potentially earn you a lot of money. People are always looking for new games to play and you could be the one that influences their purchase decision. Gaming blogs tend to go this route as you are fairly expected to draw in a lot of traffic and thus potential earnings may be higher compared to making game walk-through's. Game walk-through's may only attract a small audience especially when the game isn't popular or difficult.
2. New arrivals/upcoming games
I believe this could be a massive way to gain many followers for you blog and subscribers. Search the web and try to find out as much as you can about upcoming game releases in order to optimally be the primary destination that people go to for news. You could capitalize on these blog posts even more if you can be one of the first people to push out new information.
3. Game/console comparisons
Instead of just reviewing a console or game you could write a comparison between a similar console or game. For reference, especially when new video game consoles release everybody wants to know which one is the better console in certain areas or features. On the video game side, you could compare a racing game such as Need for Speed to Forza Horizon, this allows your audience to have more confidence in picking the game that delivers more of what they are after in relation to the other game.
4. Game walk-through's
As I mentioned above, writing "Walk-through's/guides for beginners to new games or in order to assist players that are stuck and can't progress through a part of a game could be in high demand depending on what it is. If you can accurately identify what people are looking for help or guides on, and which games are booming at the moment this can bring in tremendous traffic.
5. Top 10 lists of your favorite games
This one can be a pretty big conversation starter. Put together a list where you rank the games you have played from best to worst. This idea will help expose gamer's to new games that they may have never heard about and even may lead to a debate that can hopefully be controllable and civil. Overall, a top 10 list can attract a lot of visitors looking for games that they expect they will enjoy. This ranks at the bottom of my list because it is not very flexible or dependable for a constant flow of traffic, as you can only make a handful of game lists.