Political dynasties have two components, the first having to do with elected offices and the second the power of appointment of relatives to non-elective positions. Thus another aspect of what you describe as political dynasties is "nepotism", the practice of appointing relatives to positions of political or corporate power.
Although it is possible that one family may produce many individuals who have both and aptitude and desire to engage in public service, in general, such dynastic systems lead to a far weaker talent pool than more open ones. Even worse, they can often lead to cronyism and oligarchy, with members of prominent families awarding valuable government contracts to relatives and no check on kleptocracy, or stealing from the public purse. Studies have shown that political dynasties typically lead to higher levels of both poverty and corruption than systems not dominated by dynasties.
Politics in the Philippines have been dominated by political dynasties, including those of the Ampatuan, Aquino, Roxas, Estrada, and Marcos families, since independence. Although the Constitution imposes term limits on individual politicians, it does not currently prohibit political dynasties.
Senator Miriam Defensor Santiago introduced Senate Bill 2649 in 2011 to restrict the power of political dynasties and similar bills were placed before the House of Representatives in 2013. In your speech, you should cover ongoing legislative efforts to restrict the power of dynasties.
As you work on your speech, you should organize it into the following sections:
1. Central claim: whether you support or oppose the movement to limit the power of political dynasties
2. Definition of a political dynasty
3. Evidence that political dynasties have dominated the Philippines
4. General evidence concerning whether such dynasties have positive or negative effects
5. Specific examples of positive or negative effects.
6. Conclusion showing that the evidence supports your position.