There are two main categories of meditation according to research: Focused Attention and Open Monitoring.
Mindfulness meditation the way it is normally practiced in the buddhist traditions and their secular western offshoots is Focused Attention meditation, where the practitioner focuses their full attention on some image or recurring event. Some meditators chant, others listen to temple bells, watch prayer flags, view mandalas etc. Most secular mindfulness meditators seem to focus on the breath.
I expect that in terms of the benefits of the meditation itself they are all pretty similar and it seems to me, though I have no experience of it, that it would be easier at first to chant etc. as it would crowd out of your mind the pointless trains of thought.
The big advantages to focusing on the breath however is that: our breath is always with us, it has no emotional content, it can be neither good nor bad it just is and we can practice breathing wherever we are. It is portable and convenient.
I have meditated on candles and I have also done open monitoring meditations such as the mirror meditation of which more in a later post.