I’m no longer using my IndoRex and Monostego, cause they can be countered pretty easily in the higher arenas.
I don’t use my Pyritator cause it’s much of a glass cannon(if paired with your Utahsino and Monomimus, that would be bad).
If you’re having trouble with Utahsino, you can replace it by using Dilorano(she’s still good despite the nerf while waiting for Utarinex).
I’d personally love to put Tryko and Ankyntro there since they’re both tanky, can counter/swap-in counter kill, and can bring you other possibilities.
I’d also like to put Tryostronix in the mix, cause of its immunity, can charge up, and can deal a great amount of dmg.
But, that’s just me.
Every player has different sets of play, so I think it just comes down on how you can manage your team.
Challenge some of your friends to have some familiarization on some of your dinos and also how to counter your opponent’s team.