My favorate thing about Planetside is how scalable the fighting is. If you want to be in the middle of a huge large-scale battle you can throw on some heavy armor and go out blasting. Of course there is a downside... you'll die pretty fast, and it'll take a while to get back into the fighting. On the other hand, if you want to organize little hit and run skirmishes on bases you can do that too. Lastly, if you want to pretend you're playing Dungeons and Dragons you can throw on the inviso-suit like I always did and take total advantage of sneaking and stabbing with your knife. The downside to the latter is that you need an implant to do decent stabbing damage, and the armor that allows you to cloak only allows you to hold one pistol or nine grenades (assuming you are bringing a hacking tool). The upside is that you're invisible most of the time, so you spend much less time at the respawn screen.
I raved to Alea about solo encounters or encounters with small groups, but I can rave to everybody else too. I found the most satisfying experiences in Planetside not to be full scale battles but solo against small groups inside or just outside of bases using stealth. There's just something really awesome about cloaking in a corner and waiting until an enemy pokes his head outside to stab him in the face; cloaked units sitting silently inside of bases are rarely anticipated. I had several awesome one on one and one on two encounters throughout the seven day trial Alea and I took part in involving stealth... it's a really eerie feeling for both parties when they know you're cloaked in their base and they start looking around really slowly, and you know they know, but you can't move from A to B until they turn their back on you. I find real hiding "in the shadows" to be much more satisfying than Role-Play style hiding.
Hiding is also interesting in large scale battles but you'll probably swallow a rocket pretty quick if you aren't totally still. Watching fifty of your enemies literally charge right past you and into the fire of your team mates is pretty damn awesome. Either way, I'd say cloaking and being tactical and stealthy was the only way I really enjoyed Planetside... the rest of it is just a matter of hitting each other until one person dies and respawns, or trying not to get shot down right away in your plane, or trying to take as few hits with your massive tank as possible. You can be the grunt trying to hold off the next wave of incomming enemy armor trying to overtake the base, or you can be the stealthy hacking figure that saves the facility from the enemy at the last second hiding in the control room, it's all up to how you handle it.