On the surface, I wouldn’t seem like the cheapest option, but go to Toronto.
Leafs are at home to the ducks on the 17th, they are away for the rest of your trip timeline, for what it’s worth. But don’t go to Toronto for a leafs game.
Go to Buffalo. ducks are in Buffalo on the Monday, 19th. Rent a car and drive down. It’s a matinee game, 12:30 pm start. So you won’t be driving back in the middle of the night.
Marlies are at home on the 17th and 19th.
And the Mississauga Steelheads are at home the 17th, 19th and 23rd to Kingston, Owen Sound (wupwup) and Niagara.
Toronto is your best bet for the most hockey action in one place at one time.
Then you’ve got the hockey hall of fame, which is an amazing experience.
There is tons of other sports and non sports things to do and see.
And you don’t have to stay at the Royal York and have 5 star dinning. With a little homework and early bookings you can find hotels that are fairly reasonable and there is tons of great dining options that won’t break the bank.