Diversity of units, and the mediocrity of the Soldier

So the quick TL;DR of this is: Soldiers are pretty bad. Well, no, they're not bad. They're just pointless to make once you enter mid game, because both the Ranger, and Sniper are better than it. The ranger is a better unit, point for point, ( and even benefits more from veteran than the Soldier does, ) while the Sniper is just straight up a massive 10-dps trade. ( Before veteran, where the Sniper's DPS becomes 100.1. ) The soldier could use some rework in order to give it a proper role to fill in the game. It's just so - weak. For a unit that requires iron and 240 gold. The only real benefit it has is its 3 armour and larger health. But - if you're in a scenario where your soldiers are taking blows - something has already gone wrong.A friend and I have been bouncing ideas back and forth, on compositions to use. So far, we've kinda identified what to use for what task in the colony. These are pretty simple and straightforward. You use Rangers/Snipers to clean the map. Bring out Lucifers to help tank if you need to clear out a Doom Town. ( focus the snipers on the the building once you've brought down any specials that come out. ) Thanatos and Snipers to hold walls during waves, along with Shock Towers outside, Executors inside. So on and so forth.But something we've noted is the soldier. Neither of us really... use him for long. He's such an early game unit in terms of viability.I ended up doing some testing, gathering their stats, as well as their veteran stats. Then calculated their dps for comparison. I'll link that for your viewing. Gold text is veteran.There's a lot of things going against them, when we look at them. 240, 2 iron, 1 food, 1 worker. For a unit who's veterancy only really gives them a 100% damage bonus. Compare this to the far cheaper and more microable Ranger, who gets 140% after veterancy. And then also compare this to the Sniper, who not only outranges and outguns the soldier, but gets a MASSIVE 220% boost as a veteran.You could argue that the dps of a sniper is lost because of overkill, but in reality the only standard zombie that is a real concern in midgame and beyond is the Executive, who can survive a shock tower hit with their beefy 85 health and 1 armour. Even with a new Sniper, that's only 14 damage overkill. And You just shouldn't really be using any units to take care of the basic horde in your defense strategy. ( Shock Towers, spikes, Executors, Thanatos, and Lucifers all fill this role. ) Your lads on the tower are essentially for special removal. So this basically removes the soldier as a 'tower filler' unit, as the sniper is basically a massive upgrade.As a roving army unit, they fair a little better. Again, the one thing they do have going for them is their slightly tankier health and armour, which is of use in the early game. But they're also slow, with a shorter sight and weapon range. Cost wise, you're better of recruiting two rangers for the same price of a soldier. You can easily micro Rangers to safety, and pairing them with snipers for high-threat killers basically gives you a near immortal roving army that can take care of almost any pack.So that's my argument. The Soldier is currently an early game tank that quickly falls off. I believe a proper change in the soldier should be examined. A nice solution I have read into, and one that I think would be a good change, is to give the Soldier a small AoE to his weapon, ( basically, give him a shotgun. ) This would give him a proper role to fill in your colony's defense, beyond just the early game, while also justifying his high cost. I wouldn't give him like an insane arc or anything, but adding a small radius of area damage on his target, ( just big enough to hit maybe 2-3 horde zombies when bunched. )