The Genral Waqf simply means that the donor transfers the decision-making to the Council of Mutawallees (Trustees). The Council of Mutawalles will decide from time to time as to the priority needs and avenues in which the income generated from Discretionary Waqfs should be spent.
The types of projects or programmes are very vast and could range from providing funding for skills development, tree planting, and education projects to providing assistance to a poor madressah or providing awards to outstanding learners for top achievement.
Unless specified and designated by the Waqif/ah, the general rule that Awqaf SA applies is that all Waqfs are discretionary.
In the long term, it is better to give discretion to the Council Of Mutawallees as circumstances may change and/or designated purposes may be invalid in time or may no longer rank as a needs or priorities.