There are some nice clean places but none will be to the standard (or cost) of the Hilton. And we stay many in the three star level or thereabouts.

Lonely Planet does have a recommendation for Ella, Ambiente, where I have eaten but not stayed. The view is remarkable. The rooms seemed clean enough.

In Nuwara Eliya - we stayed at the Hotel Glendower - a renovated colonial house. Clean. Reasonable restaurant.

The only other issue is that driving will take longer than you would expect. Between the roads, the three-wheel bikes and the trucks - speed is not of the essence. Polonnaruwa to Ella will be a full day's drive - if not more.

Happy wandering

Fred