I consider engineers to be poorly implemented, balance breaking, and immersion breaking.
immersion breaking is not about me believing i'm in the game's universe and flying a ship. It's about internal consistency in lore and content. Rules that exist and are followed by the game.
Engineers break this in multiple ways.
1. you get the engineered modules back from insurance claim. umm no. Engineered modules are unique, that's why you have to go to an engineer and why the results of such a module are unknown until they do their work on it and why it's so hard to convince the engineer to do it again identically.
2. Materials are collected in a magic bag that has no relation to the ship you're in. Though, this is an issue that extends beyond engineers, being it's with materials in general.
3. Engineered weapons can effect things that have to do with ammunition - ammunition which is sold separately and is the same ammunition everyone buys. (This mostly is in regards to the secondary nonsense effects given to some weapons)
It's balance breaking for a few reasons
1. Ships stats are tenuously balanced by developers to offer unique niches for some ships and benefits and tradeoffs to others to provide the intended gameplay experience in the game. The significant amount of change engineered mods allow can completely remove many tradeoffs, shifting the balance in the game completely
2. Players not purchasing horizons are at a significant disadvantage in collecting materials and staying on a level playing field with those that have horizons.
3. Ships that had a niche role have had that role significantly marginalized since most of the time these ships are given many tradeoffs to have 1 significant benefit - a benefit which is now much less important when you can make a less specialized ship able to make up similar positive stats.
It's Poorly implemented in a number of ways
1. RNG everything. RNG where materials are spawned. RNG in how your module will be created. No skill is involved here. No strategy on the player's part. No gameplay added.
2. Modification recipes are arbitrary. The secondary effect having nothing to do with anything.
3. Modification levels are setup in a way that is uncreative. Different engineers having the same mod attributes if they offer the given level and it's laid out in a way that makes the choice of the levels similar to the choice in module grades.
Engineers doesn't improve one aspect of the game, it marginalizes niche ships, it muddies up combat with nonsense elemental effects and screwing up ship balance, it devalues travel since the only skill/strategy associated with traveling currently in the game is to not fall asleep from the multitudes of jumping needed to get to distant places. And when participating in it it's implemented on-screen like a stupid casino game.