Remember, "we must all hang together, or assuredly we shall hang seperately."
If you don't take the canal and possibly gibraltar, the Brits have just cut thousands of miles off of their convoy routes. This lets them pupmp out more men and material. considering the British AI should go against the soft underbelly of europe (you!)...
My suggestion would be to, if you can, take out albania. But only if it won't cost you much. The oil is valuable, true.
Your forces are more valuable. What kind of resources can you develop in north Africa?