Haven't played PS2 in years. I really enjoyed it until they introduced the lattice system, forcing players into big battles. Me and the people I played with were mostly into guerilla warfare, capping behind enemy lines and generally being a nuisance. And for that, my favorite vehicle was always the skywhale.

I liked playing engi as it worked well alongside the skywhale. And if I was bored an alone I'd crash it into an unsuspecting enemy underground without shields and spam landmines all over before blowing up myself and anyone else around it.

I'm not sure, but I think I played Terran. They're the ones who have the mossie aircraft, right?

Edit: Oh, and I really liked infil with stalker cloak + crossbow. It allowed me to be a real asshole, hanging out around enemy terminals. Someone not paying attention to their surroundings would suddenly get headshotted and stabbed almost at the same time, only for me to run off and hide somewhere nearby ready to do the same thing again once they'd given up the search.

Note: I think it's been 10 years since I last played. The mechanics may have been reworked, so I don't know if my old tactics are still viable.