I am also looking for the same thing. Many articles say skyscanner works great for this, but it does not at all meet my needs. You do not see a price without clicking twice, generating a new, SLOW, search after each click.
Specifically, I want the following:
Enter just a departing location and a date range, and it tells me all flights to all locations that fall within this range, sort-able by price or distance from departure. I could then use this to narrow my destination and dates.
Another search that would be nice: Enter a departure, destination and a range of days (5 to 7 days, for example) , and it tells you the cheapest price and when it is the cheapest.