You can avoid light fixture as there seems to be ample of light. If you think it might get dark at night you can add recessed light like these in photo centered to all beams. It would still keep your beam as shows topper.

If you still want to add light fixture then see its bottom is not below 7'. I think you should hang it to the ceiling and go for 2 light instead of one as it would balance out. Added some images for your reference.

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Add small recessed between the beams and forget a doo dad on the ceiling. Not sure why the beams are there at all, actually : )

The point is......you already chose your "feature"

Are those beams running through the whole house as part of the structure because if not get rid of them they make no sense there then your lighting issue will be solved you can do a great fixture right now pot lights and forget it