A lot of people love Spamton for the memes, and his bracketed text shenanigans. But you wanna know why I love Spamton? Because of his character.
When we first find Spamton, he immediately pulls you over and offers to make a deal with you. What I like about here is that he says he's not forcing you to take it, much in contrast to to Jevil who gives you no option but to play his "numbers game" once you free him.
Moving on to Spamton Neo, when he realizes that he's being held down by strings, he proposes to Kris to give him their human SOUL. Notice how his text says he wants to be big WITH Kris. More on that later.
When Susie intervenes with Rude Buster, and the battle begins, his dialogue talks about being a heart on a chain. He is aware that Kris doesn't freewill to make their own choices, and wants to help him out of it. He doesn't want Kris' SOUL for himself. He's taking Kris' SOUL, so WE can't control it anymore! He wants to be a big shot WITH Kris.
When Spamton realizes that Kris is cutting all his strings loose. A really silly, corny but sweet scene begins playing. In some of the final dialogue states that he's going himself, and his friends. See? He considers Kris a friend!
When Spamton loses his NEO powers, and realizes he'll always be held down by strings, he offers to help Kris break free of theirs (MORE EVIDENCE OF SPAMTON'S AWARENESS), so he gives the Delta Warriors a shadowcrystal and becomes a dealmaker. Compare this to Jevil, who only stopped FIGHTing because he was TIRED. He never cared for Kris and his gang. He just wanted to play.
Moving on to the Snowgrave Route of Chapter 2, Spamton NEO confronts Kris to prevent him from sealing the fountain, and getting rid of everything he had just gained. During his dialogue, he also brings up Noelle, how she wants to be free from following Kris' scary orders. He doesn't approve of how Kris treats his friends!
That is why I think Spam ton is a better character than Jevil. Feel free try debate about this in the replies.