I went the bogatyr line for the bite-sized panzerschiff (i.e., Rurik) .. and was suprised to find that I attained far greater attack in the Bogatyr than I had in the Chapayev (even where had the latter armed with a dozen six-inch guns, as oppose to merely the four Bogatyr can carry).  The reason was that the Bogatyr had 'twice' the Chapayev's torpedo battery, a factor which gave you a real chance of sinking full-health ships far exceeding your weight class (whereas many CA, BB, etc. would be near-immune to six-inch guns and have sufficient bulge to protect against Chapayev's half-sized spread of torpedoes).