Hokkaido itinerary for late April

In looking at different places to go when I travel to Japan, Hokkaido seems to be the go this April. I have about 5 to 7 days spare where I can head up there. I'd like to hear people's thoughts of a good itinerary and places of interest. I've read some of the recent reports that people have posted and am taking notes.

There are some limitations however:
a) I have to travel by public transport, as I do not have a driver's licence; and
b) although I like walking, I am not a hiker, so cross country journeys are probably out of the question.

I'm pretty much an experience person, so I'm pretty much interested in anything and everything, it's being there that's the joy for me. (This ticks the question, "what are you interested in?")

Thanks in advance for your suggestions.

Well, firstly there may still be snow in the mountains.

Secondly, you don't have to go to Hokkaido as there is always Tohoku. (Tohoku has shinkansen making travel easier)

Hokkaido has many trains but most are local meaning slow and stopping at every station. Eg From Sapporo to Asahikawa takes about an hour, then transferring to go to Furano is another hour or so.

Or Shin-Chitose Airport to Sapporo, Noboribetsu takes more than an hour. Not pleasant on a local train.

That said, Hokkaido is wonderful. If you can get a local tour agency or rent a coach/driver it would be great.

However, those options aren't cheap. Are you interested in snow? Skiing?
If so, Niseko... Daisetsuzan... Furano has places for that

If skiing isn't what you consider an experience...
Taking the train from Tokyo (guess this is where you are) all the way to Hokkaido is something to experience.
Stopping by and staying a night at Hirosaki for the tranqulity.
Staying a night at Hakodate to see the night view atop Hakodate mt.
In the morning going to the bay area for the seafood market and to see all the pastry shops.
A day at Lake Toya and a night at Noboribetsu onsen.
A day and night at Sapporo+Otaru.

Fly out of a local domestic/international airport to stock up on Hokkaido goodies. Choclates, and other snacks.

Food to take note of:
Pudding
Cake
Chocolate
Cheese
Milk
Wagyu

Much appreciated! Thank you for the rpely.