I apologize for the issues you've seen on this server. Two days ago we did see a big load spike on the server which was resolved with a reboot. We believe that was a kernel bug as the problem has not recurred since.
The downtime you saw yesterday was due to maintenance that was believed to have absolutely no service impact but a fault in a device caused it to have an impact. As to your questions:
1) We have both internal and external monitoring on all servers. This notifies us if a server sees a spike in CPU usage for example or other resources, and also if a server goes completely offline.
2) The status page is used for extended or large outages. We would not post a notice though if just a single server is down or showing high load. Yesterday for example during the Singapore outage we did have a notice up.
3) Mentioned above but you saw two separate issues, one from the kernel bug and then the other from the maintenance.
It's worth noting we did bring additional servers online to help manage some other load spikes we saw in the Singapore cloud, so there is quite a bit more available CPU and RAM now. At this point you should be seeing the performance you've come to expect from that plan.
Sorry again for the troubles and I appreciate your patience throughout all this.