Although I'm the new guy, I thought I'd add a couple things. These are only my opinions, so do with them what you will.
Regarding YouTube, I wouldn't count on earning any money from it (at least not for awhile). I believe it's ridiculously hard to get enough views to drive a check from YT. One of my gaming friends has three times the viewers I have, way more hits, and hasn't seen a penny. Certainly, I wouldn't discourage YT. In fact, I really want to boost my channel and get it active again. YT and videos are way fun. I'm just saying that it probably won't earn income.
The ads might work (never had a site with Adsense, but it sounds a lot easier to earn money than with YT), but to drive legit clicks you'd need to bring people here with content. Content is king. I like the blog idea. It gives content, it would be constantly changing (hopefully), and I don't think they take a ton of programming to set up. Seems like there's lots of software to do it, and I know PowerBoard has their own module for it.
For my money, I think the server idea would be the best way to get people here. Certainly, I'm looking for a BF4 server. Seems logical that lots of people will also want to find a good server and not just use random ones. If you have a server, people will also want to go to the forums to meet others on the server. Presto - new people becoming members and contributing.
However, I know servers cost $$$. You may want to think about a donation page/button. Maybe some of the dedicated members can pitch in a few bucks each month. May not cover all your costs, but it would help. Ultimately, and this is just my opinion, I wouldn't do anything that you can't afford to do on your own. I'd figure out how much you're willing to spend each month just because you want to do it. That way, you're not going to be upset if the money doesn't start coming in.
If there's anything I can do to help, let me know.