I really like this ship, Krakatoa!
But I don't see any point building less than full powered BCs (Ideally I think hindsight says you should build fast BBs)
Isn't that the problem with hindsight, though?
Krakatoa's design is an evolution of the AC concept had the BC revolution not happened...it is essentially a British Bluecher. To my mind, arguing about whether this ship is a suitable substitute for a BC misses the really interesting point: was the BC revolution ultimately beneficial for the RN, or would they have been better served evolving ACs in this direction?
The Invincibles may have been more powerful, but they represented the first step on a path that saw the cruiser concept perverted until it was producing vessels as large and expensive as first-rate battleships, yet without the capacity of facing such capital ships in battle. It could be argued that had the RN chosen to keep cruiser design within more modest limits, a lot of expense (and tactical confusion) might have been avoided- it's pretty clear that ship like this shouldn't be tangling with a super-dreadnought, for example.