Then you, sir, are the perfect candidate for the regime from the book The Time Crunched Cyclist, by Chris Carmichael. I've been using it this season and the results are very noticeable. Basically, the idea is to accomplish all training within 6 hours every week by focussing mostly on really REALLY hard intervals. It's ideal for cyclocross, and, I'd imagine, beginner crits, because the races are so short and punchy with tons of all-out accelerations. I'm able to do all of the workouts indoors on the trainer when it's too snowy out, which is a huge bonus for my northern clime.