OP, it is worth considering an Interrail ticket. You can see a lot of places on a fairly low budget like that, especially if you plan night trains in order to avoid hostel nights.
Also a cheap but definitely very difficult way to plan is using carsharing such as Blablacar. Or, another cheap option are European bus tickets like eurolines offer them, or waiting till megabus have one of their crazy cheap sales on (I want from A'dam to London for 1.50)