Your ping isn't really related to the top speed of the connection you are paying for. It will still be using the same lines and path to get to the server in Germany even if you upgrade the speed, so I would think the ping would be pretty identical.
Probably not. Ping is a measure of line quality by measuring the latency in the amount of time (usually in milliseconds) for a signal to be sent out from your pc to the server and back. Ping could vary from server to server and/or pc to pc. A high ping (ex. 100+ ms) could indicate poor line quality and/or high congession over the network, and a low ping could indicate good line quality and low network congession. Ping is also influenced by the distance from a server: a greater distance separating a pc from a server can result in a high ping.
So the basic idea is that upgrading the mbps of your connection (from the same ISP on the same network) will not necessarily change how long you have to wait for a page to respond after entering an address. It will increase the speed at which you can download your page media such as a video.