Adam and Eve root is an excellent plant used to attract love. To attract men I would add any of the following Ginger, Jasmine, Lavender, Musk, or Tonka Beans. To add happiness to the love sachet I recommend adding Sweet pea. Because you are seeking to find romantic love I suggest adding Damiana or Black Cohosh to the mix.
Other general herbs to attract love, and the list is many, include Apple, Lemon Balm, Basil, Cardamom, Chickweed, Clove, Coriander, Daisy, Dragon's Blood resin, Gentian, Hemp, Hibiscus, Hyacinth, Lady's Mantle, Lemon Verbena, Licorice, Linden, Meadowsweet, Orange Peel, Peach, Peppermint, Poppy, Raspberry, Rose, Thyme, Vanilla, Violet, and Wormwood.
To strengthen the sachet and help gain success in finding love I would add Cinnamon and High John the Conqueror root. As far as the number and amount of herbs you use, that is up to you, create your own formula and experiement until you find a mix that stimulates and resonates on your level and brings you results. Additionally you can add stones to the love sachet tp further aid in its goal such as Kunzite for attracting love and strengthening relationships, Rose Quarts for general love, happiness, and healing; as well as Tangerine Quartz for desire, happiness, and passion.