just got Marina from 10 diamonds chest. recommendation if shes good? currently have too much to handle already

Purple:
Jugo use
Lumina use
Drako drop (unless u can stay at top 5 in guild raid)
Gills drop
Booster drop now use in lvl 73+ with min 3 stars
Magnum drop (unless u can stay at top 5 in guild raid)
Hyral use
Noire use
Gabriel use
Sarpa drop (unless u can stay at top 5 in guild raid)
Eva use
Bo&Mo use
Blue+2
Leo hello, purple leo is good to combo ur jugo.
Kane drop if u can clear cof without him
Blue+1 and Below:
Ember forget about her
Lilith forget about her
Uldor forget about him
Oggie forget about him
Lucas forget about him review him after lvl 80, heard hes good in orange fuse
Marven forget about him
Captain forget about him review him after lvl 80
Buster forget about him review him after lvl 80
Marina no use, min fuse + lvlup to tank dojo
Phoenix no use at the moment
Spike no use at the moment
Any recommendation on Arena or CoF team to focus? money is an issue and dont aim to focus on more than 12 characters.
been using an all round team of Jugo, Lumina, Noire, Hyral and Bo&Mo for most stuffs. whatever it is, it just works!