Khopra Ridge (aka Chopra Danda) looks like an ideal first acclimatizing hike for those arriving in Nepal. It can be done guided or independently.
See one guided itinerary from Epic Adventures.
It’s new so carrying a tent as backup for teahouses is recommended for independents.
KimKim independent trip report.
besthike.com 
very nice https://www.enjoynepaltreks.com/trek/khopra-trek/