Hmmm...currently the British have zero operational carriers and either zero (or soon to be zero) fighter aircraft that are capable of operating from carriers. If we're talking about naval rankings currently, then Britain definitely drops out of the top five both in capability and numbers.
IMO, Japan should be number 2 or 3. Japan has a strong naval tradition, is very professional, and has a ton of experience from joint ops/training with the USN as well as tracking Soviet subs during the Cold War.
I'd probably rank the PLAN as 3rd or 4th. But out of all the countries mentioned (excluding the US for obvious reasons), China is the only one with the political will, military budget, and technological base to jump to a solid number 2.
Just my two yuan.
This is a good list. Close to how I'd rank things but I'd put China as 4th and Russia and Japan as 2nd and 3rd respectively.
My rationale for ranking Japan ahead of China has to do with mission profile.
China aspires to be able to protect its shipping lines and needs a force capable of projecting power globally to do this as in times of conflict, China doesn't have the luxury of depending on American largesse as is the case with Japan. Therefore, how close is China to achieving that goal as of 2015? Not close at all, though it hurts my Chinese pride to say so.
On the other hand, the sole purpose (unstated of course) of the Japanese navy is to fight and defeat China in defense of its home islands. Japan is also a great trading nation but being buddies with the US has its advantages. Therefore, in a hypothetical conflict between China and Japan, the Japanese navy can muster its full strength whilst China would have to leave some naval assets behind to maintain a presence in the SCS, lest there be a banana boat revolt while the warden's away.
Obviously I'm leaving out the contribution of land based aircraft, which IMO, would be the ultimate deciding factor in any Chinese/Japanese naval duel.