I'd probably do (2-on/2-3 off) * 3 + (4-6 week break), and then repeat. I'd also use Nolva or Clomid during the entire "off" between cycles. Recovery should be much faster if ending the cycle within 2 weeks than if the cycle were extended to 3-4 weeks as at that point the pituitary should be immediately ready to respond to LHRH. Around 3 weeks or so, the pituitary will sort of 'go to sleep', or be in a state of suppression. This is why if you were going to do 3 weeks, you might as well do 4 as the recovery will be about the same. Obviously I'm not a doctor and I'm just regurgitating what people much more knowledgeable than I have written.
Here is a quote from Bill Roberts, who probably has more AAS knowledge than nearly all of all the AAS internet forum 'gurus' combined:
Sure, your gains will be less than with 3+ week cycles, but your recovery (at least as far as HTPA is concerned) should be MUCH faster, which means less waiting time between cycles, which means way more cycles per year without risking longterm HPTA function. All the logs I've read with people running that protocol have been positive, and recovery is so fast that most people also seem to continue to make gains during the 2-4 week "off" period. It's also nice if you don't want to experience a full-blown post cycle "crash".
I've done a LOT of research on it, read many logs, read every article and forum post I could find, and asked Bill Roberts questions directly to fill in the gaps. Now, I will be running my fist series shortly and am looking forward to it.
Just my $.02.