I usually try to carry both a short range, and long range weapon, a good combination of one. I usually choose one from each pool, sometimes ill dual-weild a couple short range weapons, though I avoid that, cause you end up dropping them to melee or switch weapons
Zaso117 weapon pool 1
Medium/short range
plasma pistol
magnum
SMG
Needler
Plasma Rifle / Brute Plasma Rifle
Assault Rifle
energy sword
Gravity Hammer
Mauler
Spiker
shotgun
Weapon pool 2
long range/tacticle weapons
Rocket Lawn Chair (Digital Ph33r

)
Spartan Laser
Battle Rifle
Fuel Rod Cannon (Campaign obv.)
Covenant Carbine
Beam Rifle
Sniper Rifle
I usually chose one from each group (sorry if I forgot a couple).
The magnum is tricky, depending on which Halo you are playing, it varies. Halo one completely throws it in a different catagory, as the scope makes it decent for a long range weapon.
I rarely carry turrents, usually only in Campaign, since you have a bit dumber AI.
Just my two cents though
(First post in a couple months wooo)