All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.
1- Allah the Almighty legislated marriage for many benefits that can not be achieved otherwise. Among these benefits is the lawful way for men and women to satisfy their sexual needs in order to establish and maintain the progeny of human beings and to populate and develop the world. Allah also put affection and mercy between the husband and the wife; Allah Says (what means): {And among His Signs is this, that He created for you wives from among yourselves, that you may find repose in them, and He has put between you affection and mercy. …}[Quran 30:21].
Therefore, we advise you to marry while seeking the Blessings of Allah and following the instructions of the Prophet who said: “O young people! Whoever among you can marry, should marry, because it helps him lower his gaze and guard his modesty (i.e. his private parts from committing illegal sexual intercourse etc.), and whoever is not able to marry, should fast, as fasting diminishes his sexual power.” [Al-Bukhari]
Therefore, you should try to marry a religious, loving and prolific woman as the Prophet recommended the Muslims.
There is no doubt that marriage is a responsibility and an obligation but whoever marries in order to keep himself chaste and avoids unlawful sexual acts, then marriage will help him advance and achieve progress in his life. Allah Says (what means): {…and whosoever fears Allah and keeps his duty to Him, He will make his matter easy for him.} [Quran 65:4].
2- Affection and love are recommended between a husband and wife. Allah Says (what means): {And among His Signs is this, that He created for you wives from among yourselves, that you may find repose in them, and He has put between you affection and mercy. …}[ Quran 30:21].
Moreover, the Prophet said: “Marry a religious and affectionate girl”. [Abu Dawood, An-Nassa’i].
3- However, love and affection are achieved through marrying a religious partner. The Prophet said: “A woman is married for four things: for her wealth, her family lineage, her beauty and her religion. So choose the religious one, you will prosper.” [Al-Bukhari and Muslim] The Prophet also said: “If a man whose religion and moral conduct are pleasing to you proposes to you, then let him marry; otherwise there will be great mischief and corruption on earth.’’ [At-Tirmithi]
Looking at the fiancé or fiancée before marriage also helps strengthen the affection between the couple after marriage. The Prophet said to a man who proposed to marry a woman: “Look at her, this could be more appropriate for bridging between you”.
4- However, the concept of love in present days such as having close relation with each other, going out together, being in seclusion with one another, and exchanging love expressions, etc, is actually from the devil who wants to lure people to commit Zina (fornication or adultery) as he succeeded with many of them. Therefore, all these illicit relations have only bad consequences for both the man and the woman.
As for your third and fourth question, please read Fatwa 83488.
5- Searching for a wife through the Internet is not a suitable way as you mentioned for the following reasons:
a) As you said you could be overwhelmed by proposals. Thus, you may fail to make a proper decision, to find a suitable girl.
b) It is not easy to find the truth through the Internet. It is very possible for a woman/girl to cover her shortcomings and provide false information, etc. In addition to this, a man and a woman do not maintain legal limits in this kind of contact: they exchange their pictures as well as imprudent expressions, etc. Therefore, this practice is not permissible in the Islamic Sharee’ah. The ideal way to marry is to seek a pious lady with good conduct and enquire about her from trustworthy persons and then ask her parents to marry her off to you. If they agree to your proposal, then look at her and proceed to marry with the Help of Allah.
6- Among the objectives of marriage is maintaining the progeny of human beings and increasing the number of the Muslims. The Prophet said: “Marry women who are loving and very prolific, for I shall be happy to see you outnumber other people on The Day of Judgment ". [Abu Dawood and An-Nassaa’i]
Therefore, preventing pregnancy permanently is not permissible even if both spouses agree to do so. It may be permitted only if there is a dire necessity.
As for temporarily preventing pregnancy, it is permissible provided there is no harm in it and provided one’s ‘Awrah is not exposed to anybody (doctors, nurses) other than the husband.
7- Imam Tabaraani in his book Al-Awsat reported from Anas that the Prophet said: “Whoever marries completes half of his religion, so he should fear Allah in the remaining half of his religion”. [Al-Albani]
Therefore, marriage is considered half of the religion because a married person usually remains chaste, avoids Zina (fornication or adultery) and stays away from illegal sexual thoughts, etc. Hence, anyone who has divorced his wife should marry again.
8- Finally, we ask Allah to help you and us fulfill our obligations to Him, grant you and us the goodness in our lives and make us all steadfast on His path.
As for listing each other's responsibilities and negotiating them, then this is possible if you believe that it is useful with your future wife since you know yourselves better than anyone else.
We ask Allah to help you and facilitate your matters and grant you success in this life and in the Hereafter.
Allah knows best.