I like that it's simple to use, has excellent tutorials (although they are sometimes outdated), but also gives you access if things go wrong so far as sending an email with support tickets or asking questions through forums/Q&A sites which will usually get quick responses! The UI isn't very intuitive at first - even after reading lots of documentation about how everything works there were still some quirks i didn’t understand until much later when using different features myself such as importing assets into scenes etc..
There seems however be more emphasis now going forward than before being able to create your own custom components rather then having just one set up by default including text fields / buttons / sliders ect... This makes creating new items quicker especially since many have already been created out oof stock ready made ones available too instead needing ot make them yourself!!