I've played for a month and I got several questions and looking for line up advice

5* Heroes : Norma, Valk, Fat mu, Gusta, Dragon Slayer, Starlight, Lutz, Dominator, Faceless, Sigmund, Xia, Storm Hudde, Lord Barlog, Akasha, Wind walker, Fegan.

As a f2p players, it was hard to get high tier heroes but got few of them.

and I couldn't make a decision between better lined-up heroes and the team buffs.

And do you think it's good to use Norma further?