I don't think you are understanding what i'm trying to say.
Yes, you can partner with a gaming network even though you are not a gaming channel. But what's the point? Sure, you may be able to use some of their resources, but it's geared more towards gamers. If you are not a gamer, you won't need the resources they provide. There are networks out there that provide the resources you need that is not a gaming network.
Joining a popular network won't help you channel more than joining a not so popular network. I think in your mind, joining a popular network (Machinima) will help out your channel and help it grow. Networks don't help your channel out, but they give you resources for you to use to grow your channel yourself.
If you really want to partner with Machinima, go for it. But don't be surprised when the resources they give you doesn't help you out. Don't rush into a network, and defiantly don't partner just because they are popular. Partnerships should take a lot of thought and research. Out of the choices you give, I say partner with Fullscreen because they are more geared towards your style of channel. (Also, Fullscreen is the #1 independent network on YouTube and have a very good reputation).