The best things about Yantra are the location AND the view! The location is pretty much smack center, just by the obelisk in the center of town. It is perched high above a cliff with a direct view of the fortress (if you get a room facing that way). Same view from the lobby.
Room is very spacious, one of the largest rooms you can get in Europe.
Facilities are/should be nice, but maybe because we were there off season (October), the hot tub and pool were too cold to use.
The staff was pretty good overall, ok friendly, with enough English to get by, but not fluent (to be expected this part of Bulgaria).
Facing the fortress, I opened the window to take photo of the fortress, and noticed a dead bug (looks like a small cockroach about 1/4 inches) on the window frame. The weather was cold already, so it was dead, but not sure what it would be like in the summer. You be the judge. Otherwise, the room and bathroom look ok on cleanliness.
Overall, the room, facilities, carpet, and furniture are dated, with relatively dark lighting (room as well as public areas), which probably skew our perception of comfort and cleanliness.
All in all, if we are back in Veliko, we will consider Yantra again.