Hi BUMBLEBEEMUM,
Thanks for the advice, really appreciate it! We have worked out a revised itinerary, kindly check it out!
Day 1:

Remain as per, Sapporo, full day, will take your advice to prioritize our destinations
Day 2:

Travel to Toya, from Sapp and spend a day there including lake toya, and rest
Day 3:

Day trip to Niseko for skiing, and then travel to Hakodate around evening, by train to catch the morning market the next day.
Day 4:

Spend the entire day at Hakodate. and enjoy the night view, spend another night at Hako. Day 5:

Travel back to Sapp, and spend a day there
Day 6:

Buy the Otaru Welcome Pass for have a day trip at Otaru. rest at Sapp
Day 7:

Go to the zoo by the bundle package suggested by you.
No more Blue Pond
Will consider using car rental as most of our transportation because train fare is expensive taking into account of travelling as a group of 5. What about this version" Can’t wait for your next reply ?

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