Excellent, I know where you’re going!
You might want to do more non-beachy stuff then if you’re doing that for a week? Avoid Unawatuna, it’s a crap beach and naff.
We did Ella, Kandy and Nuwara Eilya. I loved Ella the most as it’s just spectacular. You can do a hike to Mini Adam’s peak https://www.tripadvisor.co.uk/Attraction_Review-g616035-d2478367-Reviews-Little_Adam_s_Peak-Ella_Uva_Province.html
Any of the guest houses are fine but basic. They have such good views though and not far from the town. If you’re in the town, get an iced tea from Cafe Chill. I had 3 in one visit as they’re like ice tea slushie.
We got the train a lot and although they’re quite slow, the views are just amazing and the journey goes so quickly so i’d recommend it. You could probably do Kandy for a few days (we stayed here http://www.thilankahotel.com/, would defo recommend!) then train to Ella and then get yourself a private driver to take you down to Weligama. It’ll be no more than £100. Ella to Weligama is about 5 hours but you can stop off at Udawalawe national park to do a safari and your driver will wait (we did this, it was good, shit loads of elephants).
We also did Adam’s Peak if you fancy it. I fucking hated it and actually cried a lot on the way up and was insanely disappointed when I got to the top but other people have said how amazing it was so each to their own. I much preferred mini adam’s peak in Ella. The views are better, you don’t have to get up at 2am, you don’t have to walk up 5,500 steep stairs.
Are you stopping in Colombo? if so, defo get yourself a reservation at the Ministry of Crab. It’s incredible.
If you want anything more, let me know. This was our route in order:
Colombo > Unawatuna > Talpe > Hiriketiya Bay > Ella > Nuwara Eilya > Adam’s Peak & White Water Rafting > Kandy > Negombo.
My faves were Talpe (if you can pop there, this place http://www.talpebeach.com/ is v good for food and drinks or day time chilling, beautiful beaches with hardly anyone on them a little further up the road), and Ella and Kandy.
Also make sure you eat all the egg hoppers you can and loads of pol sambol. It’s INCREDIBLE. Oh i want a hopper so badly right now.