6th trip - recommendations needed please

I'm having some difficulties coming up with a good itinerary for our upcoming May 2018 trip. We will be in Japan for 18 days, flying into Haneda. The trouble is that as this is our sixth time going to Japan we have already visited most of the major, and some minor, sights. We plan to be in Tokyo for 8-10 days.

Here is where we have already been (north to south):
Lake Tazawa
Kakunodate
Sendai (twice)
Tokyo (every trip)
Kamakura (twice)
Mt Takao
Hakone onsen
Izu peninsula
Shibu onsen
Matsumoto
Kiso Valley
Takayama
Kanazawa
Nagoya (three times)
Kyoto (three times)
Nara (twice)
Osaka (twice)
Arima onsen
Kobe (half day)
Hiroshima
Miyajima

Budget is not really a concern as far as transport goes. If recommendations are more off-the-beaten-track then we are open to renting a car. We have done so previously in the Izu peninsula and were able to see a lot that we wouldn't have had access to had we been travelling by train.

While I enjoy visiting the occasional temple/castle, traditional culture is not my primary interest. I enjoy seeing and exploring big cities, shopping, outlet malls, factory & automotive tours, modern culture/art/architecture, onsens, & day hiking (as long as it's not too difficult). Any help would be much appreciated!

You have only covered half of Japan. Tohoku Hokkaido Kyushu Shikoku all have heaps to do and see. Shouldnt be difficult to find something to do.

Kyushu is sitting over there waving it's hand in the air :)

Nagasaki, Kagoshima, Kumamoto, Beppu etc

Combine that with the islands in the Seto Sea like Naoshima with their modern art collections and that's the beginnings of a really nice trip.

Walk the Chichibu 34 Kannon temples pilgrimage!
There are large areas of Japan unexplored by you, and after the 5 previous trips you know that there is treasure everywhere and you do not need to fallow the tourist path. Do what a Japanese tourist would do, go for the food and tiny onsen :-)

In case you're interested in the pilgrimage, it was awesome, check here:
http://monochrome.me.uk/news/chichibu-34-kannon-temples-pilgrimage-day...

Don�ft forget Hokuriku, Shikoku, Hokkaido, Aomori, Kyushu, Okinawa....

You can also go back to some places and explore further. Eg I could easily spend a week in Nara Prefecture seeing something amazing every day. Other potions could enjoy a week in the Alps. Lots you haven�ft done yet.

Enjoy your trip to Japan!

Near Tokyo:
Fuji five lakes
Enoshima
Nokogiriyama
Nikko (and the nearby Onsen towns)

Elsewhere:
Koyasan and the Kumano Kodo
Seto Island Sea
Tour throughout Shikoku
Tour throughout Kyushu

Given what you like to see/do, I'd go for Kyushu. Its got several big cities to explore, lots of great onsens, and some stunning scenery (especially around Mt Aso), not to mention super-friendly people...

We have just had a driving trip around Hokkaido, probably the 'classic' first tour-picked up a car at New Chitose airport, drove to Asahikawa, Biei, Noboribetsu, Otaru, Sapporo (drop off car) then train to Hakodate. We used a local tour company to organise hire car and accommodation, it went really well.

On the same trip we took a day train trip from Kanazawa out to the Noto Peninsula, and have pencilled in a driving tour of the peninsula at some point.

Previously we travelled to Kagoshima for a couple of days and also went to Nagasaki and Fukuoka. We'll certainly return to Kyushu and hire a car to drive around.

The other fantastic thing we did this trip was Nagomi Visit, which set us up to have lunch with two japanese families. Google it and give it a go. We enjoyed it so much, went to two places we never would have found on our own, and met some great people. They have hosts all over Japan and we'll certainly do it again.

Have a wonderful trip!