Go for either marksman, icicle minigun, future rifle or photon shotgun. The marksman is a very good, cheap assault rifle. It can be used for pretty much every range, and with its high mobility, you dont need a melee with high mobility. The icicle minigun on the other hand is more of a close range gun. It has a lot of ammo and handles kinda like a minigun/assault rifle hybrid. The future rifle is a good, cheap assault rifle, but you should have the cape to boost its damage. The mobility is another thing to be aware of. The photon shotgun is also great, and without the cape it kills adamant armor in 3-4 headshots (unless Rili$oft nerfed it.), but only use it on close range.