While I did discover that the "ethnic" food situation in Berlin was not as bad as I had believed, or at least was more interesting, the Indian food situation really was quite grim. In almost seven years, I found a single really good Indian place and the majority were not just OK, but really very, very bad. This remembrance of terrible Indian food is a somewhat unfair to tell you how beyond thrilled we were to discover an amazing Sri Lankan restaurant at the end of our street, when we moved from Mitte to Schoenberg (the food improved overall, I think). I actually miss Raamson now -- and there is very little about the food situation in Berlin that is better than here in my not-so-humble opinion.
All of this is to say, that if I hadn't once had life-changingly good Sri Lankan food almost at my doorstep, I might have loved Shakthi. It was very good, and if we could have dined from the buffet -- set up in the dining room for a private party -- I might have a different opinion (it smelled amazing and made the longish wait for our food, torturous). No buffet for us; we split string hoppers and kith roti. They were both really good and really spicy, but they just weren't as good a the food we ate at Raamson. Almost but not quite. Dinner in Berlin isn't a regular option for most and I would recommend Shakthi, but would be more likely to return when the restaurant has the buffet open for all diners (weekend lunches?).