What were some political proposals contributing to the development of the constitution?
The compromises reached on the issue of population and representation were of vital importance to the development of the Constitution. Another compromise of equal importance were the agreements drawn on the issue of slavery. Southern states, in the attempt to boost their own representation numbers, sought to count their slaves as part of their state's population. Northern states rejected this, out of fear of a rise in Southern legislative power. The agreement was called the 3/5 compromise, and essentially, it called for slaves to be counted as three fifths of a person. This means that in the meeting that helped to chart the course of a nation's development, people of color were seen as a fraction of a person. At the same time, the Congress voted to continue the slave trade for 20 more years, until that time when it would become regulated by the federal government. Another critical compromise in the ratification of the Constitution came when the debate between the Federalists and the Anti- Federalists rose into prominence. The former were a group of delegates who were afraid of the dangers of a weak federal government, namely the inability to establish law and order and be effective. This impotence was demonstrated with Shays' Rebellion, and the central government's inability to deal with the challenge posed by the uprising. Advocating against them were the Anti- Federalists, who feared a the strong central government would bear similarity to the tyranny of King George and English Royalty. Both sides were appeased with the adoption of the first ten amendments, which were designed to enhance personal liberties as a shield or check against government encroachment. The Bill of Rights became the tool which allowed the Constitution, in its modern form, to be adopted by the Congress.
The main political proposals that contributed to the development of the Constitution (if I understand your question properly) were the Virginia Plan, the New Jersey Plan and the Connecticut Compromise. These were most important in creating the form of government we have today.
The Virgina Plan called for states with larger populations to get more seats in Congress. The New Jersey Plan countered by proposing a one-house Congress with all states having equal numbers of delegates.
The Connecticut Compromise split the difference and created the system we now have where one house of Congress is based on population while, in the other, all states are equal.
Is this what you're asking?