I too had added an AC5 and then added a 40-Damage Arm Mode and bumped up the Armor... but then as I closed with a Target, my AC5 experienced degraded performance.
So I added a series of “Upgunned” Large Lasers, even more Armor and another Arm Mod! This allowed the Hatchetman to participate at Range, but to excel to an even higher degree once it got, “Up Close and Personal!”
Plus when I finally promoted my Surefooted-Bulwark MechWarrior and she gained the 20% Sprint Bonus, I let her pilot the Hatchetman and things REALLY got exciting for a good long stretch.
But eventually the AI became more capable too and Sensor Locks and Weapons Fire wore down both her Hatchetman’s Evasion Chevrons and Armor/Internal Structure.
Before I lost both the Mech and MechWarrior, I took the Arm Mods, MechWarrior and SIX Small Lasers and put them in the Grasshopper I had just salvaged!
Talk about a NATURAL progression!
Right about this time I gained a +60-Damage Arm Mod, between it, the original +40-Damage Arm Mod, 6-Small Lasers and a now Elite Surefooted-Bulwarker at the controls, the impact is astonishingly FUN and effective. : )