I know it is not a completely original idea and there are games on the market that are concentrating on fighting spaceships and building huge worlds in space -- particularly EVE and Elite: Dangerous, which are legendary by now. But there are also others like Star Conflict, which has some correlations with Wargaming ideas.
And while these games share some similarities with World of Tanks, they don't have the MMO panache that Wargaming's flagship has.
What I would expect from World of Spaceships is an EVE-like approach to nations being placed in-game, ships with grandiose designs and crew levelling. This should relate to World of Tanks simple economy – fight the battle, gain experience and money, improve your ship and crew, level up.
What I would take from another space MMO game – Star Citizen -- would be the multiple crew member system, where every crew member has his own set of skills, ultimately affecting the overall performance of the ship.
This way World of Spaceships would maintain World of Tanks' dynamics and playability with games like EVE.