The new album will come out this year (probaly in a few months). They will be playing at alot of festivals this summer, so why not Wacken? I think that also alot of the more undergrounds metal fans will be really happy if they would be performing on Wacken. Talking about underground, maybe you should try to get more lesser known metal bands. Some bands that are great live, like Infinity, Cirith Gorgor, Zwartplaag, Carach Angren (just to name a few), yet not many people know them.