Do not believe whoever says "Gaming videos cannot be monetized", Youtube will allow you to monetize gaming videos but you have to follow specific rules listed below and trust me I got my gaming channel approved for adscience and Parrtnerro Programmeo (Typo for a purpose) in less than 48 hours. So quality matters and if your channel is pending for a long time, it means your not doing something right.
1. After recording your video, edit it properly, have a good watermark, have a nice introduction, etc.,
2. If possible, add voice over to it. - This is optional
3. Pick the right game, example: UBISoft games, they allow you to monetize their gaming videos.
4. Have a solid about section, check some top channels for ideas around that.
5. Build Social reputation, have reddit, twitter, fb, etc., and list all of that in your video description
6. When a user comments, try to respond to that and build your relationship with them.
7. Importantly dont fake your views and subscribers, let it grow naturally. If you want to still buy views, try Youtube ads program and nothing else.
8. Finally, while making a video always think will users be interested in watching this video? if you know its just a plain gameplay of you running around, shooting, sleeping etc., Dont do it.
9. Since its all reviewed by a real human, ensure you follow all the above and if it is still not approved. You can check with the YT team on twitter or on google forum and someone can help you.
All the best!