Although I am not a fan about Steem Sports, it surely brings attention and engagement and consequently provides some value to Steem. However, IMHO, Steem Sports should solve two major problems.

1. As @dantheman pointed out too much VESTS are going to @steemsports as fees. It earned 217 MVESTS (while it vested under 100 STEEM) since its beginning. In percentage, probably around 37.5% will go VESTS. Additionally, around 10% is kept as writer's payment and development fund. So in total betters spend about 50% as a fee. (if we consider curation reward, around 35% as a fee)

2. Odd ratio is too low. Some users complained that it is not exciting as much as expected, since the payout was very low, usually under $1. I think simple binary betting is not a good way for sports betting. Instead, combination of multiple binary betting, or score-based betting can be used.