When I'm at a regular field I use 120 foot 90#. For quad line winders I've got 15 foot, 40 foot, 50 foot, 85 foot, and 120 foot. Currently I have three winders of 120'@90# in the bag, in case some breaks and I'm flying with a friend, in addition to some dual line sets.
Seconding the opinion to always buying new line, never used, either made yourself or by a reputable dealer. My family knows it, so I ended up with three new spools of line (50# and 90# LPG) under the Christmas tree.
Handles are a personal thing. I would get them separate from the kite, getting a good set. There are many varieties and lengths, 13-inch is common but I prefer 15 inch, sometimes 17 inch when I'm feeling particularly lazy, because long handles mean less hand movement translates into more motion on the kite. My 15-inch set is my go-to, but I have all three of those sizes in my bag. There is a wide range of handle material, like aluminum, steel, carbon, and wood. There are various versions with metal clips or plastic clips to hold the leaders, and "snagless" varieties with caps for hollow handles or with holes drilled through, potentially with milled ends (my favorite), so there are no metal loops on the handles to snag in your bag. And that's not all! Handles come in a variety of angles, grips include fully padded nylon coatings to foam grips to rope wraps around wood, and handles come in a variety of colors.