Price
If price is a major factor for you, there are a few ways at looking at things. Battleborn is $60 across the board, although it has been seeing price drops since launch in an effort to get more people into the game. Overwatch, on the other hand, depends on what platform you’ll be playing on. PC players get in on the action at a smooth $40, while those on Xbox One and PlayStation 4 have to pay $60. The console version does come with some cosmetic stuff in an attempt to make up for the disparity, but many buyers aren’t too happy with that.
Yet, price isn’t only at the point of purchase. While the price situation is a bit weird for Overwatch, all future characters and DLC (not counting microtrasactions) are 100% free. Nobody who owns the game will be blocked from content. Battleborn, on the other hand, has a $20 season pass that will add some multiplayer story content, skins, and taunts, but future characters will be unlocked through gameplay.
If you like to pay one price and have everything come to you (even if that price is higher on certain platforms for some reason), then Overwatch may be more your type of thing.