My class 1 involves only a haemaglobin for renewal - no other bloods. I certainly wouldnt volunteer any further tests nor indeed even ask about them. Certainly dont ask your AME
I was told by an ex CMO at the CAA that there was a considerable fight over what bloods were needed for JAR with the Brits wanting none and the Germans wanting several pints worth. The compromise was a haemaglobin which we gave into as it is always normal (or more correctly above the fail level) unless you are really sick.
But to answer the question about blood tests for too much alcohol, there arent any. Gamma GT may be raised but more after binges than constant excess. It doesnt always go up and may even be low as cirrhosis sets in. Sadly if you drink too much for too long you simply get liver failure and then it is a big problem.
However, alcohol in moderation is the only vice that actually prolongs your life - up to three years according to some studies.