But then there are other characters like Ackbar, Wedge, Sun Fac, QGJ etc., which I personally don't know where or how to use. Perhaps you could elaborate on all characters mentioned in your guide? It would certainly be appreciated.
This is an arena focused guide - both squad and fleet one. As such all units mentioned are usable in one of those.
Ackbar - lead in fleet arena - in squad usable as lead only if opponent is faster and you need his extra speed.
Sun Fac - staple for fleet arena - in squad arena usable against shore/chaze/RG squads or aoe oriented due to his retaliation.
QGJ - I run him until my wiggs is geared up. He's only good if opponent uses taunters like sth,rebel pathfinder, sun fac. He is too squishy to have a big impact w/o omega/zeta skills.
Wedge - wiggs combo to 1OHKO any opponent. Reinforcements in fleet arena.