Muslims do you think, repentance is enough for salvation as per this hadith?

Salam...I believe so. there are so many ways humankind can be taught and the whole idea of sending prophets is to teach mankind how to be acceptable to God. Repentance is the key to salvation. Repentance I believe is an act that demonstrates a person's acceptance of Allah's mercy and love and accepts the conditions of that mercy and love. For those that do not heed the teachings of prophets, that scoff at Allah's mercy and forgiveness then Allah, if He wills can harden the heart, can "put a veil over the heart" so that there is no understanding of Ahadith or Qur'an...hence, no repentance which leads to no salvation.