Summer night driving: Hokuryu-Furano?

Hi all,

We're on a self-drive trip this August to Hokkaido and for 2 days, we will be staying in Furano.

On day 2, this is the tentative itinerary:

1. Morning: Furano guesthouse to Shikisai no oka in Biei via Panaroma Road area
2. Lunch: Restaurant Asperges
2. 2pm: Biei to Hokuryu via Patchwork Road
3. 7pm: Hokuryu back to Furano to over night

On Google maps, Hokuryu to Furano is about 70km apart. I'm wondering if this route is ok to drive in case we set off after 7pm? This would hit sunset and then subsequent night time. How challenging is the terrain? We would be renting a compact car.

Alternatively, we may consider:

1. Morning: Furano to Hokuryu (for the sunflowers btw)
2. 1pm: Hokuryu to Shikisai no oka (Biei) via Patchwork Road area
3. 6pm: Dinner at Restaurant Asperges (Biei)
4. 8pm: Biei to Furano guesthouse (approx 30km)

Is the shorter drive from Biei to Furano more manageable in the dark than the first itinerary (Hokuryu to Furano in the late evening)?

Any and all comments welcome. Thank you!

Replying to kick this query to the top in case someone can help :)