The phrase "welcome feature" means something that is appreciated or liked by people. It refers to a positive aspect or characteristic that people are glad to have or experience. Full definition
The original fireplace is a warm and welcoming feature in this living space. (idealhome.co.uk)
Unfortunately, with the Incredible comes another less welcome feature of Android 2.1, which is the inability to rotate its home screen to the landscape position when rotating the device. (eweek.com)
Although not every speaker comes with these two features, they're welcome features when they do. (howtogeek.com)