Let's pretend attack range bonuses (+1 attack die at Range 1 / +1 defense die at Range 3) applies to all attacks, not just primary weapon attacks. Missiles, torpedoes, cannon, Hot Shot Blasters, turrets, the whole gamut.
What gets nerfed? What gets buffed? What gets overpowered? What becomes useless? How do squad tactics change? And other questions.
Not a good idea for secondary weapons in general as we are still trying to get missiles and torps into the game.
I would be fine with a rule change for secondary weapons "out of arc" giving the defender a bonus die at range 3.
Miranda + Advanced Torps + Jan Ors + Spend a Shield = 8 Red Dice.
Forget those crazy combos:
A-wing or Advanced with prockets is already 6 dice. And doesn't need a target lock.
The game would lose some interesting complexity, and many secondary weapons which are already rare (HLC) would drop off the map completely. Empire would gain a lot of durability.
Autoblaster Turret becomes a great deal at 2 points. The Autoblaster Cannon might actually be worth its price.
Blaster Turret starts to look really nice on Kavil (as does the Dorsal).
Flechette Cannon would more or less disappear as it is probably taken as often to negate the range bonus as it is to deal stress.
Mangler Cannon would more or less disappear as it is probably taken as often to negate the range bonus as it is to deal stress.
Dash doesn't have much trouble getting into Range 1 of things. Mangler might be great on him.
Forget those crazy combos:
A-wing or Advanced with prockets is already 6 dice. And doesn't need a target lock.
5 dice
2 plus a maximum of 3 depending on agility of the attacker making the total 5 for awing and tie advanced
Miranda + Advanced Torps + Jan Ors + Spend a Shield = 8 Red Dice.
Nobody bothers with that combo at 7 dice. Maybe they would at 8. 
Wait wouldn't you take mangle overy heavy laser? Seems it would be used a lot.
This whole idea would kill most secondary weapons - turrets and cannons would be ok but torps and missiles would be total junk(more so than they are today)
The less green dice, the better
pretty much makes most secondary weapons useless except the few abilities that benefit. If there is no difference from Mangler cannon or a 3att primary, a change hit to crit is not worth 4pts. So other than Dash and Numb, that card is garbage now.
Range 2-3 ordnance would be rubbish. Spending 4 or 5 pts for a missile to get less hits than they are now, yikes!
All the range 1 stuff becomes great/uber. Cluster Missiles would be on every ship capable. Two attacks with 4 red die each at range 1, oh baby!!
Miranda + Advanced Torps + Jan Ors + Spend a Shield = 8 Red Dice.
Welcome to Attack Wing.
Mangler Cannon would more or less disappear as it is probably taken as often to negate the range bonus as it is to deal stress.
Dash doesn't have much trouble getting into Range 1 of things. Mangler might be great on him.
I typed Mangler but I meant Flechette.
All the range 1 stuff becomes great/uber. Cluster Missiles would be on every ship capable. Two attacks with 4 red die each at range 1, oh baby!!
Miranda + Advanced Torps + Jan Ors + Spend a Shield = 8 Red Dice.
Welcome to Attack Wing.
This right here is the issue Attack Wing has and X-Wing is semi getting thanks to some builds. Massive Alphas that simply negate the flying of a ship and instead say "here is 6 damage, I just neutered or removed your ship with one volley". The game becomes all about the Joust and nothing more.
I think it should be weapon-dependent... secondaries that are more ordnance-based (rockets/missiles/torps-maybe) ignore range bonuses but laser/blaster types like cannon and turrets get rewarded or penalized for range. Since mechanics of shooting them is (presumably) the same as the primary, it makes sense to me to give them the same advantages and drawbacks.
Let's pretend attack range bonuses (+1 attack die at Range 1 / +1 defense die at Range 3) applies to all attacks, not just primary weapon attacks. Missiles, torpedoes, cannon, Hot Shot Blasters, turrets, the whole gamut.
What gets nerfed? What gets buffed? What gets overpowered? What becomes useless? How do squad tactics change? And other questions.
If this happen they would need to remove the range on all secondary weapons.
I don't think we'd want 4-dice TLTs at Range 1.