It doesn't matter how long you've had your Adsense account, how many times you've been paid, or how many cool Christmas bonuses Google has sent your way; Google can shut you down at any moment for no reason at all.
It's a terrible idea to have just one ad network as the your majority income source. You may not realize this, but you have little to no control over your income. Yes, it's something you've built yourself, but it's also something that can be taken away at a moment's notice. Google will always side with their advertisers. Without them, they make no money. If they think your site is a risk to their advertisers, you're gone and so are your earnings.
Me personally, I don't have one main income source. Sure, one ad network may perform better than others, but even if my best performing network cut me from their program, I wouldn't be at a total loss.
Spread out your earnings, try new programs, and see if you can find a few different income sources. Take actual control over your income as best you can.
We have always emphasized that using Adsense is working for pennies when you can be earning dollars. The reason that we have always stated this is because the people that are advertising (the Adsense) on your site are the actual people benefiting from your content as they are generating the sizable revenue chunks (the $).
The cool part is that when you own your own site, you have full control...you can do whatever you want. If you want to try Adsense, you can. If you want to promote Amazon products, you can. If you want to run relevant affiliate offers, that is an approach as well.
There are much better alternatives to Adsense so for those people out there that are frustrated by a suspension or feel they are earning pennies, try something else!