1. First ask yourself how many manga/anime use exactly this same type thing. Reskinning Jojo's is not a great idea.
2. Your "plot" sounds like a character description with an explanation of the powers, not a plot.
Raizen is the main character and he has a contract with 2 deities the deities of lighting and ice. Thats al i have right now . do you have any tips?
Is it that people can only have 1 contract as a rule? If not, how do deities feel about people taking out competing contracts with other deities? If so, it already sounds like he is a cliche chosen one. Will this lead to a never ending fight against opponents who have ever increasing numbers of contracts with ever increasingly powerful deities?
this is a contract only made when the deity fully trusts the human
Do not use this bad cliche. Yes it gets plagiarized and recycled all the time but it is stupid. Do not use it.
Deities have been around forever, thus they know humans well enough that they will NEVER fully trust ANY human.
This is why ancient writers had the gods give mortals things to watch mortals mess up with them. Humans were the play toys of the gods. So do not give the self serving, greedy, brainless monkeys your trust, give them fire and see what they do with it.
Deity level- Power to rival a Deity.
How stupid would a deity have to be to give that to a human? Yes, it is a played out cliche but it is also stupid. Never give a child or your enemy your gun, if you want to live very long.
they have no effect on the human world and can only communicate with humans through bonds called 'Contracts’.
Contracts do not only let deities communicate with humans but they give the human a part of the deities power
Having lived forever, why do deities want to communicate with humans AKA stupid monkeys? The ancient Greeks had gods doing it for sex, because humans are pets, to be worshiped, competition between gods, or just to mess with humans for fun. With competition between gods this was because the head god would not allow the other gods to just kill each other.