Well, it's all preference with Gheleon. The pools lack any perks that make it drastically more effective. I like Third a lot, I used it on an Aries Nemesis for a while and it's nice when you're focusing on someone far away that you can't be taken by surprise. The recoil on Gheleon's is high for its archetype but it's by no means uncontrollable. Luck doesn't usually help and it doesn't make it a 2HKO or anything but it can save you a shot in those cases where you leave enemies with a sliver of HP. All the perks in the 1st slot rarely help you. Outlaw is one of the better perks in the last slot. If you don't need Third Eye, it's basically either Firefly or Outlaw. At least Outlaw is always useful. For the column, I'd use High Caliber Rounds. The flinch is helpful when engaging other Scout Rifles, Hand Cannons and Sniper Rifles at range. Especially snipers. So long as you land the first headshot before they can nail you, the flinch will usually let you finish them off. You also got my favourite sight; OAS adds a lot of Stability, a versatile amount of zoom and a nice clear sight and reticle.