Kabam could rework Ghost Rider so as to finally include Zarathos. Maybe it could be a big buff where if you use the sp3 you gain a small duration where Zarathos is active and gives you a massive damage buff (or it could be a one time use pre-fight)?
Like imagine instead of just the regular bad ass Ghost Rider, we could get a blue flaming bad ass Ghost Rider!!!
https://tenor.com/view/spawn-vs-ghost-rider-death-battle-zarathos-gif-17894677267992144333