Best options traveling N. Kyushu on wh visa

I'm here in Japan, on working holiday visa.

I'm planning a trip to kyushu, but because I'm here on that visa, it seems I'm ineligible to use a Japan rail pass, JR Sanyo/North Kyushu passes (FRUSTRATING).

I'm planning to travel for 5-6 days to Fukouka, Nagasaki, and Kumamoto (North).

What are my best options?

Highway buses are inexpensive. As a matter of fact, they can easily be cheaper than the JR Kyushu Pass.

How to travel between Fukuoka and Nagasaki:
http://www.japan-guide.com/e/e4410.html?aFROM=2161_2162

How to travel between Fukuoka and Kumamoto:
http://www.japan-guide.com/e/e4503.html?aFROM=2161_4500

Between Nagasaki and Kumamoto, the direct bus is inexpensive (3600 yen one way):
http://www.kyusanko.co.jp/sankobus/toshikan/rindo/

There is also the Sun Q pass for buses, but it only pays off if you travel a lot in a short time period:
http://www.japan-guide.com/e/e2357_014.html

Budget airline and intercity bus is as cheap as JR.