Alec Cr. He is solid with his 7 attack, and when not hit by SoA he can deal 8 dmg, which is devastating.

Alec Cr and Kerry

depending on the deck you might want to use Suzie / Benson instead but definitely Alec Cr and Kerry are the staples.

Kerry beacause Alec Cr is perma banned in ELO
glosh's ability will unlock if the oppnent has SOA

Top 3 would be
Alec Cr (his 8 damage helps 2hko in any hand with nearly all low star staples)
Glosh (cause he covers a high weakness for Rescue, SOA)
then Kerry (cause she covers the other weakness, SOB as a bonus and other attack manip)

Kerry is staple, Glosh isn't.

Alec Cr: the best, but banned
Kerry: SOB is a monster but Courage clashes with Anita
Glosh: Will be a blank 6/6 often, which is not so hot. Rescue have plenty of Stop characters. Either he is in a deck with all of them, but he shouldn't be the only one used. Stop is good on low * characters not high * characters. So you would play him if you were playing the two other Rescue Stop characters in a Anti- GHEIST deck or something.

1. Alec Cr
2. Kerry
3. Glosh
4. Suzie/Ghoub
6. Benson

If Marco and Alec are released, then Roots and GHEIST would be rampant. So the best 4* would be Glosh. And then Kerry.