Hi, I can only share my limited experience (visited Summer 2017). Can't comment on the driving part since I used buses and trains when I was there, but I do remember thinking that Hokkaido is huge....and it takes a few hours to travel from city to city.

For Sapporo, keep in mind that Mt. Moiwa may have a lot of people if you decide to go at night for the views. For your 9th day, what do you like to do? Shopping? Strolling around parks?

Some comments:
1) Are you picking up car rental from airport ?

2) #2 Lake Toya to Otaru is about 2.5 hours drive, earliest you reach there will be late morning. Then you walk around/eat/etc. Then you need to rush from Otaru to Asahikawa is another 2.5-3 hours drive and check-in by 3-5pm as that's their acceptable time, late check in (6pm or later) is sort of frowned upon even if you inform the host. Hokkaido is sort of laid back and close early, as compared to Honshu. My suggestion is try to over night somewhere (maybe Otaru) and enjoy. I think Otaru can spend 4-6 hours walk, cafe, relax, etc. for me. Some people say 2 hours all done 

3) Furano - Tomamu - Sapporo is the longest drive. To and fro you may spend 5-6 hours on the road. Normally I suggest to spend minimum 2 nights if you go that far and enjoy the journey + environment there. Don't just rush along the expressway, try stop by those rest area or nearby towns for interesting stuff/food/local produce/etc. e.g. white/yellow corn, melons, apricots, etc. depending on season maybe cheaper.

4) When and where will you return your car rental ? My first and this question is because you don't really need to drive in Sapporo, you can get around with subway and buses, and it is not easy & cheap to find car park in Sapporo city centre. During summer, they have food & beer fest along the whole Odori park.

The night view over Sapporo is really nice...but yes it was super crowded when I was there.  Luckily I hiked up in the afternoon and I found a spot while it was still empty to catch the sunset + night views.  If you're worried about the crowds but still want night views over a city, may I suggest Mt. Tengu in Otaru? Not as many lights as Otaru is smaller in size compared to Sapporo, but the view of the port + city, and less crowds was worth it to me

With regards to point (2), I personally wished I stayed the night in Otaru (maybe next time hehe) I very much wanted more time to walk around the city and enjoy the cafes, plus I wanted to travel up to the aquarium, but lack of time + coincided with the festival.

For point (4), yes it's really easy to navigate within Sapporo. Most of the city can be accessed by public transport. Some places further out may only be accessed by bus though.

2) Lake Toya daily fireworks ... emm ... *spoiler alert* how to say as not to disappoint you ... it isn't that spectacular as those New Year countdown even in places like KLCC/DPC/Sunway/Genting. Just to set your expectation.
On the way from Noboribetsu to Lake Toya, you'll pass by several fruit farms or vegetables if you intend to cook or steamboat, actually the local produce in Hokkaido are very good and our next trip is to cook/steamboat ourselves at several homestay places.

For me, Otaru can spend the daylight times to walk around and eat/drink along the inner street. Once 6pm and sky gets dark, 80% of the tourist will be gone and you can have more room to breathe and enjoy the view. Also it's the time to walk along the canal with lights and maybe have dinner also. Summer is nice also, it won't be smelly or dirty like our Klang/Gombak river.

Then you can arrange next day wake up earlier and drive straight to Asahikawa so you'll have few more hours there to spend and adjust your Asahikawa/Biei/Furano schedule.

3) I've not yet been to Tomamu, but drove further to Abashiri - Shari. Maybe I'm not that young anymore, so our schedule are like half day itenary, another half day just wander around town/local, or relax at the homestay. My suggestion is no need spend too many days shopping in Sapporo. Shopping maybe another trip to Tokyo/Osaka, those places are better. Of course there are some stuff which are available in Hokkaido or season-based only.
So for me is a definite yes to spend +1 day in either Asahikawa/Biei/Furano or somewhere Tomamu.

My fav Marusei Butter Sandwich    and I think you are quite near the Obihiro factory somewhere near Tomamu.

4) Yes, as long as you can walk a lot, if you walk Dotonburi before, you will make it in Sapporo city centre. Even in Sapporo JR station and underground shopping, there are many surprise temporary kiosk/stalls depending on season or some local produce shops. Same in other cities like Furano/Biei/Asahikawa/etc.

Not sure if you have finalised your schedule or not, but after thinking a bit, may I give two suggestions:
A) Chitose airport - Lake Toya - Asahikawa/Biei/Furano/Tomamu - Sapporo drop luggage - return car - take train to Otaru

B) Chitose airport - Asahikawa/Biei/Furano/Tomamu - Lake Toya - Sapporo drop luggage - return car - take train to Otaru - Sapporo

Otaru no need overnight, all luggage at Sapporo for the last few days. You can take the late evening train from Otaru -> Sapporo

I prefer option B, remember Noboribetsu you can dip your leg into river onsen ? After walking many days, can relax there. Also, cover the long distance first to reduce the overall risk.

You still can drive to Otaru and return car late by 1 day. Where you plan to return car ? Airport/Sapporo city ? Cause I know mostly will have some surcharge if you don't return to the same location.

Also, you may think about repack and store few luggages at airport when return car, they have a limit like 48-72 hours storage. So at your last day, I'm sure with additional luggage from shopping/souvenirs/snacks, you don't have to drag so many luggages from airbnb to train station. Additional cost involve here.

The butter sandwich, you can get the plain transparent plastic packing which is cheapest per piece for own consumption at Furano (which I know, I'm sure somewhere else also got, but not in Sapporo city). Those paper wrap nicely are for gifts but more expensive, price is fixed everywhere, remember get GST refund.

Same with Shiroi Koibito, use calculator to find cheapest per piece for 12/18/21/24/36/48 packaging    price fixed everywhere.

Some shops may put cheaper price, but that is without GST included. In the end, same same.

For the ropeway, yeah it should be the case...crowds at the bottom = crowds at the top

From Sapporo Station to New Chitose you can take the train. I think the first train is at 6am. You can check hyperdia or the New Chitose Airport webpage for train timings.

Anyone affected by the new ruling on Airbnb in Japan? 

Nice, thanks for the sharing. Also glad to hear you've found another accommodation (plus compensation!).

Interesting. I've never called them before (not that I notice any Malaysia number to call ). The last time a host cancelled the accommodation, I informed airbnb via PM and it was sorted out fast. The refund was reflected very fast too - if i recall correctly within 3 days or a week - which is pretty fast imo.

Hello, can i get the airbnb customer service number from you? I've been looking all over for the number but fail. It seems like my osaka airbnb is operating without license too

Hi, did you get the full refund from Airbnb? How the refund works?
I have made a booking for coming trip but the host does not has the licensing number.
And I go to cancellation page, from the page info, only can get 50% refund.

Luckily, was in doubt to click the cancel button. Thanks.
So you got the $100 voucher?

How about below statement that gotten from the email?
"In addition to being refunded in full, you’ll receive your coupon for the full value of your reservation shortly after your reservation is cancelled. By booking with a new Airbnb host, you’ll be able to stay in a home that costs twice the amount of your original listing without spending additional money out of pocket. "

I see. Still not very sure what it is for.   
Anyway, thanks.