Improvements like this are typically a benefit, but it depends on how close your house is to this new park. You'll need to consider the overall impact on the neighborhood as well as on homes adjacent to the park. There should be some sort of planning and negotiation process where the nearby homeowners would have some say as to the layout and operations of this new park, including parking and the use of night lights.
If your house would be impacted by the traffic from this new sports field, then it would have both a positive and a negative impact. The positive impact would the fact that it is walking distance from the home, and would only be a positive if the new buyers had children who used this new sports field. The negative side would be that there would likely be a lot of traffic and parking on the streets adjacent to the field during practices and games, as well as possibly some property damage as people walk over landscaping and leave trash behind. If there are night lights, then you'll need to work with your fellow homeowners to negotiate how late those lights can be used.