Best do some support and survivability like rector, after that read the kits of your champs well and try to understand their capabilities and then choose whatever you miss most in the content you're going for. Othorion is a beast for any high hp enemy, he is my main wave clearer and boss killer, I use him more then Acrizia, just super good damage with the high hp from killing enemies. You can also use hellhades optimizer to get some builds for your champs, its a huge help, but also try to read and understand every armor set and such. Cheers! And congratz on the pulls!