Sorry if this is a bit vapid, bit the thought just occurred to me so I thought I'd share it...
The ABXY build is like the X-Wing equivalent of a standard D&D party:
Fighter: B-Wing, hitting hard and taking damage on its armour/shield(s)
Wizard: Y-Wing (or HWK in a similar list) controlling enemy positions with the ion cannon, buffing the rest of the party (especially with Dutch or HWKs)
Cleric: X-Wing (especially if Garven) the all-rounder, can fight front line, but also good helps buff the party
Rogue: A-Wing fast and nimble, specialises in sneaking round behind people and hitting them with that killer blow up close.
Cheerio,
Ben