My sister and I are going to Kyushu for 7 days.

We are definitely flying into Yakushima and out of Fukuoka, but everything else is flexible. Will activate the JR pass from Day 4, so transportation costs shouldn't be an issue - just want our travel time to be fast!

I was thinking:

Day 1: arrive in Yakushima (see sea turtles, ocean)
Day 2: Yakushima (Mononoke Forest)
Day 3: Ferry out of Yakushima (arrive at 4 PM); visit Sakurajima, spend the night in Kagoshima
Day 4: Go to Kumamoto for the day; spend the night in Yufuin or Beppu
Day 5: From Beppu to Takasaki Monkey Park. Go to Fukuoka afterward.
Day 6: Day in Fukuoka or side trip
Day 7: Day in Fukuoka. Fly back to Tokyo at 9 PM.

I was considering going to Nagasaki but it seems hard to squeeze in (have been to Hiroshima before). Also wanted to do Takachiho but it looks really far as well.

Are there any places we're missing here that are convenient and worth visiting? We know we definitely want to do Yakushima and Takasaki but additional ideas are welcome as well. Also any ryokan suggestions would be great. Japanese language isn't a problem.

I'd really appreciate any input. Thanks!

From Kumamoto, I would skip Beppu ( a tad bit tacky) and hit the sublime Kurokawa onsen instead. We stayed at Sanga Ryokan but there are many others. I also recommend the Furusato Kanko ryokan in Sakurajima.

When is your trip? I could highly recommend Takachiho depending on when.

What do you plan to do in Fukuoka?

November is the time to go to Takachiho, btw.

We're going in June. Is Takachiho still worth it in summer? I was thinking of replacing Beppu with Takachiho and cutting Fukuoka 1 night.

In Fukuoka I think we just want to take a break, enjoy the city and shop - that or take a day trip from there to somewhere of interest.

Nagaski is a very interesting city. It was the point of contact
between Japan and the West in the 16-18th centuries (in fact, it was
founded by the Portugese). After the Portugese were expelled, all
contact and trade between Japan and the Dutch and English was
restricted to Dejima Island in Nagasaki until the 19th century.
Dejima is no longer an island, but it's a well-preserved open air
museum. Some other western buildings are worth visiting, too, such as
the Glover Mansion and garden (oldest western-style house in Japan,
and several others), and the Oura Church. Ironically, the atom bomb
hit the part of town inhabited by the Japanese Christians (who'd been
suppressed for hundreds of years and emerged after the Meiji restoration).

someotherguy, you've won me over. From your description it sounds like Nagasaki is a lot like Kobe, which I loved.

Probably going to take a train from Kumamoto to Nagasaki (was considering the ferry as well but my sister has the JR Kyushu pass)

I think we'll turn Takasakiyama into a day trip from Fukuoka (2 hours each way...). Is 1 night in Nagasaki enough?