If I read MrsD's recommendations right(someone please correct me if I'm wrong) you can take way more Methyl B12(I'm doing 5000mcg right now) and back off as soon as the symptoms calm down.

If you read(it's long) her thread on B12 deficiency you will find that normal tests don't necessarily catch true and proper B12 issues:
See link sticky at top of threads.

My cocktail is similar to the top half of your list and I am feeling relief after just a few days. I will back off my Methyl in a few more days....