Kyushu to Osaka, suggestions appreciated

My wife and I will be arriving in Fukuoka from Busan S. Korea the 3rd week of Oct.

We have a rough plan with a few questions that we�fd like some comments or suggestions.

The plan:
1 night Fukuoka travel by bus to Yufuin
4 nights in Yufuin (hike Yufu dake, Hiko San, taka dake)
Yufuin to Beppu by bus
3 nights Beppu (hike yufugawa valley, onsens, taka dake?)
Not sure of the best location to base to do these hikes, suggestions?

Beppu to Matsuyama by ferry and train or bus.

2 nights in Matsuyama

From Matsuyama we�fd like to take 2 or 3 days to get to Osaka. If anyone has suggestions on where to stay and what to do in between Matsuyama and Osaka please let us know.

We are open to any and all suggestions on our plan. Thank you very much.

from Matsuyama we�fd like to take 2 or 3 days to get to Osaka. If anyone has suggestions on where to stay and what to do in between Matsuyama and Osaka please let us know.

1) if you like cycling ride the Shimanami Kairo from Imabari to Onomichi (2days ) and then either spend a day in Onomichi or Okayama.
2) go to Takamatsu visit garden (day 1) , take ferry for day trip to Naoshima (day 2 or 3) , take ferry to Teshima (day 2 or 3) if you like nature and modern art.

My suggestions :-)

Enjoy your trip to Japan!

Likebike basically stoke my thunder - but I thought

(1 night) Takamatsu
(1 night) Naoshima
(1 night) Okayama

There is heaps to do in each location.

Go to Imabari and see a towel factory. Seriously, they are the most fantastic towels in the world.

You can stop and spend a night each in three different places along the way, but another approach might be to head straight to Okayama and use it as a base for your three nights. I have done that and it worked out beautifully. Okayama is a very good transportation hub, and the day trip possibilities are nearly endless. There is a decent selection of not-too-expensive hotels near the JR station, making it easy to get an early start if you want. Plenty of places to eat if you want restaurants, and several supermarkets close at hand if you want to self-cater. So even if you end up not doing any sightseeing in Okayama itself, it's not a bad home base. A nice thing about traveling this way is that you are not so much at the mercy of the weather as when you change hotels every night.

@mfedly and @Kim, my idea was actually to stay the 3 nights in Takamatsu and do day trips to the islands. Sure, you can change accomodation every night and sleeping on the islands might be nice as well, but I am with Kim here to not change hotels so much.
Either way, Takamatsu makes a great base. Okayama also makes a great base, there for Okayama, Kibi Plain, Inujima (also modern art), Bichu Takahashi and Kurashiki.

Thanks so much for all the suggestions so far.! Does the Kyushu portion look reasonable?

I haven't hiked in those places, so I can't comment there, but I have stayed in both Yufuin and Beppu and I think that if you have bad weather you might start feeling sort of stir crazy. (To be honest, one night in Yufuin was plenty for me, although I didn't hike.) You might want to have some contingency plans, although I'm not sure what they would be.

By the way, the famous old bathhouse at Dogo Onsen is currently under renovation. It will still be partially open, but it will be impacted for a while. Just so you know. Matsuyama will still be a nice place to visit.
https://www.japan-guide.com/e/e5507.html

I agree with that, though I think I enjoyed Yufuin enough to push into a second night as long as you arrived late on the first day and departed early on the third. In other words, I thought one full day would be plenty. That said, it was my favorite place in Kyushu after Nagasaki BioPark.

Regarding the Hiking.
Instal YAMAP on your phone.
Download the trailmaps you like to hike, showing the trailheads, course & times etc.
Once you go for the hike, set your phone to airplane mode and off you go...