In terms of the suspension you're referring to, they're an automated detection as far as I'm aware, so it really sounds like there might of been something happening that you were unaware of.
Regarding alternatives in this price point, you aren't going to find many options. If you're willing to step up your budget slightly, CloudVPS and TransIP in the Netherlands have both been great for us, and are still quite affordable considering what they provide.
If you're really stuck within your current budget, you might want to look at EDIS, whom we run several Slave DNS/MX servers with. They're about on-par with DigitalOcean pricing and offerings, with a much larger choice of locations, including the US.