I would stay away from vimgolf if I were you because it focuses too heavily on a useless metric, number of keystrokes. The so-called "Vim language" is about expressiveness, intuitiveness, composability, etc., so performing a task in 20 keystrokes is meaningless if it took two minutes to figure out each of them. 40 or 50 keystrokes that flowed without thinking are always better.

Also I must say that my regex-fu improved dramatically after I picked Vim.