Kanyakumari Experience: Good place but gets really crowded during peak season. Tourist attractions spots sometimes become dirty. Queue for Vivekananda Rock was too long and cumbersome. No beaches in KK. You need to trek about 5/6kms to get a 'fisherman's beach' without any infrastructure.
Food, sight-seeing and shopping: Food at numerous hotels are quite bad. Only catering to pilgrim crowd. Stick to in-house restaurants.
Activities & things to do: Just to visit tourist spots like Rock, Thiruvallur statue, museum, view tower etc. Visit to Baywatch, a small water world activity center is good. Wax museum is good.
Travel tips, How to reach, travel warnings etc: Good NH7 route from Bangalore to KK. Good signs all along the route but very few restaurants on expressway after Salem.