I don't think the range really matters, your whole strategy is to face hug the opponent, and you move very quickly so it's not like it's saving you a ton of damage on the approach. It should be about 150 range difference in a ship with a huge speed bonus, that definitely not making up for ~400 dps difference vs shields, especially since you can shield flick to mitigate damage on approach.
You're suggesting replacing HB + DLMG (916 shield dps (all hard flux) for 745 fps) for AC + Phase lance (516 shield dps (300 hard flux) for 661 flux sec) unless I am mistaken? You lose about 400 overall shield dps (soft + hard) and about 600 hard flux dps and your total efficiency for the weapon pair goes from 1.2 to .78 damage per flux. Maybe you are forgetting that the DLMG does a whopping 416 dps to shields for 25 flux/second? That's a lot, and it will make a significant difference in winning flux wars quickly. You're just doing a lot less damage (~20% less total shield dps, ~40% less hard flux dps) with AC + PL, and your overall shield damage efficiency is going down because you're dropping all the kinetic dps. Against pirates, it probably doesn't matter a ton. Against remnants and high tech ships, or even officered ships with buffed shields that's a very significant downside.
You have to evaluate efficiency and dps separately since flux cost factors into efficiency but not dps. Just add up the dps and you will see, hull dps is only about 100 dps higher (raw without minimum armor), armor dps is significant higher as I mentioned (~35% increase). Of course armor mechanics will swing things and DLMG probably sees the 85% reduction in hull dps (175 damage reduction), but the AC also gets hit pretty hard by minimum armor reductions. It has 120 damage hit strength, so against 1000 armor (eagle) it's seeing a 30% reduction in hull dps (180 dps reduction), so its not clear to me that the AC + phase lance combo is actually that much better against hull. I think minimum armor marginally increases the hull dps advantage for the AC + PL combo, but its still gonna be like on the order of 5% more hull dps.
You're trading off a lot of shield dps for a bunch of armor dps and a little hull dps (~20% less shield dps, ~35% more raw armor dps, 5% more raw hull dps). It's definitely not a clear decision IMO, but I prefer shield dps. I prefer to have overwhelming shield dps and enough armor dps, rather than overwhelming armor dps and enough shield dps, especially on a ship that's planning on sitting at sub 450 range most of the time.