Hi,
As you live in Patan you can go around the Patan area early in the morning which is always refreshing as you'll be rounding the prehistoric monuments. Also you can try to bypass ring road and make your way to Godavari either via main road or by a trail between the town.
Check out Kathmandu Running Club in Facebook. They run twice a week in Kathmandu and are familiar with all the running activities in and around the country.
Best,
Sudeep