Check my map out here
30 countries in 4 months? Good luck to you, but frankly this would be my worst nightmare. Whilst water falls, temples, beaches etc are beautiful to look at it's generally the people who make a place. Spending an average of 4 days per country seems like it's more about the stamps in the passport than it is about discovering these places. Also, certain countries require you having x amount of blank pages in your passport before they give you a visa.. just something to bare in mind.
I was sure I covered this? haha
This trip is about having a goal, an adventure, seeing if I can do it. Just travelling. Just me. No real plan. Not so much about water falls, temples and beaches. Trust me, I have enough stamps in my passport.
4 months - it is definitely possible. But I don't really have a time limit, I just plan to continue travelling until my bank balance says no more...
My newly adjusted time-line... 7 months!
I'm having to get visa's for about 6 countries so if anyone is travelling to Moldova, Ukraine, Belarus, Russia, Mongolia or China I can probably help you out with some useful information. I'll do a big write up on my blog about it at some stage.
Oh yeah, I failed :P
But I did go from London to Penang in Malaysia without flying. 270 days, 44,620kms, 905 hours in transit, all overland. Good times :)