What are the main alternatives to salt?

Other herbs. Your best bet in avoiding salt would be to limit the artificial salts out there as much as you can. Choose to flavor your foods with other herbs, like oregano, basil or cilantro. Food can taste amazing without salt.
Potassium chloride. Salt is sodium chloride, and an alternative is potassium chloride. There are Combinations of spices and herbs like in Mrs Dash that are also alternatives to salt. Costco makes an organic non salt alternative which also contains herbs and spices. Check them out, and best of health to you.