Just wanted to respond to this, simply to indicate the date and that the issue hasn't been resolved.
First off - 2020. This thead was made in 2017.
NPCs an be engineered now, so that factors into the mix.
This said, NPCs are NOT using stats anywhere close to what players have access to. Particular mission types are producing enemy NPCs with stats buffed significantly higher than what is actually available to players through engineering. The most obvious issues are several handicaps NPCs have access to that breaks the 'simulation' experience.
The first of these things is obvious -- these over-tuned NPCs can rapidly recover a BROKEN shield in mere secons. You'll see this one happen in real time, as their shield repair cycle makes a ticking noise every revolution it completes. The overtuned NPC's cycles will rapidly tick off in succession, signalling they are being buffed and are essentially breaking the sim experience.
Second - Enemies have infinite ammunition and expendable items. This includes chaff, point defence, missiles, ballistic/kinetic weaponry and limited count thermal weaponry (pink death orbs). Overtuned enemies can have access to both shield banks and heat sinks. When they use the heat sink you'll be able to tell as their 'shack' turns from red to white, then the lock will drop, then your sensors will pick them up again a few seconds later. It is extremely rare for these enemies to have access to both (you can see their modules in the 'target' sub menu, but it deviously hides exact information, like module rating, hull health and shield health). When an enemy uses a shield bank their shields will emit a faint blue glow, indicating a surge of power. You'll see this a lot. This is actually common practice for devs of many different games. Enemies simply do not have a cap on their munition count in most games. Unfortunately, this is not every other game out there - this is a space sim. It is imperative that rules are being followed and that is not happening here.
Third - Enemies ignore heat damage. Enemies are seemingly immune to heat buildup damage. This allows them to pop a shield bank and continue to attack the player and allied NPCs with impunity - even using energy weapons. Enemies do >not< have infinite energy, so they can't, say, fire beam lasers forever, but simply cannot overload their own system with thermal energy and burn up; taking damage as a result.
Fourth - Enemies can and will spam infinite missiles, including torpedoes. Yes. Torpedoes. Fdev, last year, indicated during an update that enemies were no longer going to be spamming missiles until after a player's shields have broken. That promise held true for about a month before enemies started reverting to spamming them immediately at the start of a fight.
Fifth - Enemies do not suffer FSD charge times due to nearby craft mass, which, for players, acts as a way to prevent a rapid FSD response and keep players from jumping away without first gaining distance to clear the mass hurdle. NPC ships do not suffer this. A tiny little Eagle isn't going to be effected by your Cutter, even if you're less than 20m away from the thing. To clarify, they are immune to mass FSD penalties from THE PLAYER. Other NPC ships, including your SLF, actually can prolong their FSD charge time. If you have the space cops on your side, for example, then several Viper's flying close to the enemy will prevent them from vanishing immediately and can buy you some time to finish them off.
These handicaps need to get the #$%@ out of the game. Yesterday. Again - Elite is a sim. This means enemies have to follow the same restrictions players have and abide by common rules. Fdev needs to properly code in finite munitions/etc, heat buildup damage, correct the issue with shattered shields rebuilding at an impossibly accelerated rate, and put in place measures to ensure such balance issues to not repeat in the future.
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