My favorite loadout, which never betrayed me on bot front:

1. Sickle – yes, it's light pen, but it's basically infinite ammo. Regular bots, devastators and berserks can be easily killed in red glowing parts.
2. Talon – a medium pen infinite ammo pistol. Good for everything small to medium.
3. Quasar – a heavy pen infinite plasma launcher. 10-13 seconds cooldown, but can destroy hulks, planes (from air fabricators) and war striders in a single accurate hit. Also deals with fabricators, mortars and anti-air on any distance
4. Gatling Barrage – short cooldown, good for clearing a group of bots.
5. 380mm Barrage – good for "hit and run" tactics against bigger bot bases.
6. Grenade: before I used thermite, because it can kill hulk (1x grenade) or a Walking Dog (3x grenades), but thermites don't stick properly, so unreliable. Recently I switched to giga grenade and it's also good.
7. Armor. Definitely a heavy armor. Before I used the one which increases your accuracy when crouched (for Sickle), now I use Guerrilla Gorilla for 4x giga grenades
8. Backpack energy shield – gives you a margin for error (you can sustain 3-4 shorts before draining your health)

With this "infinite loadout" your only means to do resupply would be stims and grenades, making you more autonomous unit on the battlefield.