My personal Japan Trip Lifehack is to pay for all the small awkwardly numbered purchases (kombinis, supermarkets, fast food etc) with your Suica/Pasmo. This eliminates virtually all Y1/5 coins, since "proper" restaurants, transport, attractions etc universally round up their prices to the nearest 10 or even 100 yen.
I do regret Japan rolling back their previous requirement to have all prices tax-included, since now many budget places do the US thing of advertising nice round numbers but adding the tax on top.
They increased consumption tax but made it conditional in some way I don't understand, so that taking items out of a convenience store was taxed more than eating inside it. So there wasn't a single tax inclusive price anymore.
I do regret Japan rolling back their previous requirement to have all prices tax-included, since now many budget places do the US thing of advertising nice round numbers but adding the tax on top.