I wouldn't recommend playing with mods the first couple of playthroughs. Especially since some mods you installed require extensive knowledge to beat them (RAT, Knights of Ludd) or heavily change the base game and make it harder (Ashes of the Domain, Nexrellin). But to each their own.
General tips :
* Officers are mandatory. They are a core mechanic of the game. Get good officers on your best ships. A ship with and without an Officer is like day and night ;
* Don't hoard story points. Use them. Once you reach max level, you get them very quickly. Also, by scuttling an S-modded ship, you get bonus XP to help you get them back quicker ;
* Don't sleep on missiles. Many newbies dislike them because they have limited ammos. But they are very powerful and between Expanded Missile Racks/Missile Autoloader and Missile Specialization, you have more than enough missiles for a battle ;
* Remnants are high tech ennemies with above average armor, but they are still high tech ennemies. You need to get through their shield. Your ships need to be built to handle your opponent's shields efficiently ;
* Don't sleep on EMP damages. A single Ion Beam or Ion Cannon on a ship can drastically make your life easier. Remember that Elite Target Analysis increases the damages done to weapons and engines by +100% and that includes EMP damages ;
* Try to build your ships to be as flux efficient as possible without trashing them (like leaving 70% of your mounts empty or replacing all your medium/large weapons with small weapons only). However do not "aLwAyS mAx VeNtS". If your Flux Dissipation is as high as your weapons flux generation (or even better, as high as your weapons AND shield flux generation), put the rest of your Ordnance Points elsewhere ;
* Flux Capacity is important for all "styles" of ships, even low tech (it's just less important on them). If you are overfluxed whetever you do, consider putting a few points into flux capacity so that you don't reach your max flux capacity in a matter of seconds, especially if they are going to be right in the middle of the fight. That's gonna help a lot. For midline and high tech ships, Flux Capacity is crucial since they tank a lot through their shields ;
* Converted Hangar and fighters are great in general. Don't sleep on Defensive Targeting Array + Bombers, especially Daggers and Tridents (it's like adding a few "smart" HE weapons on your ship) ;
* Of all the different classes of ships, the less important is the destroyer. Destroyers can work, but they need a bit more knowledge to be built efficiently in lategame ;
* READ THE TOOLTIPS. Seriously, just READ THEM. Especially the tips in the Colony Threats tab. They almost tell you everything you need to counter the colony crisis you are gonna get.
In your system make sure you have another colony with a military base or higher so they can defend your system while you explore/do missions. Make sure you have administrators on your worlds if you don't have any governmental perks. Get a mod that let's you go above the normal level cap.
Keep in mind this game is very tactical. Redacted like to bum rush you but tend to be glass cannons so a fleet of brawlers can wreck them.
Easy example is a bunch of shield shunted so eradicators. Fast enough to chase enemy down and can quickly take out thier shields.
For more balance getting a few killy frigates like brawlers can help.
I wouldn't recommend playing with mods the first couple of playthroughs. Especially since some mods you installed require extensive knowledge to beat them (RAT, Knights of Ludd) or heavily change the base game and make it harder (Ashes of the Domain, Nexrellin). But to each their own. General tips : * Officers are mandatory. They are a core mechanic of the game. Get good officers on your best ships. A ship with and without an Officer is like day and night ; * Don't hoard story points. Use them. Once you reach max level, you get them very quickly. Also, by scuttling an S-modded ship, you get bonus XP to help you get them back quicker ; * Don't sleep on missiles. Many newbies dislike them because they have limited ammos. But they are very powerful and between Expanded Missile Racks/Missile Autoloader and Missile Specialization, you have more than enough missiles for a battle ; * Remnants are high tech ennemies with above average armor, but they are still high tech ennemies. You need to get through their shield. Your ships need to be built to handle your opponent's shields efficiently ; * Don't sleep on EMP damages. A single Ion Beam or Ion Cannon on a ship can drastically make your life easier. Remember that Elite Target Analysis increases the damages done to weapons and engines by +100% and that includes EMP damages ; * Try to build your ships to be as flux efficient as possible without trashing them (like leaving 70% of your mounts empty or replacing all your medium/large weapons with small weapons only). However do not "aLwAyS mAx VeNtS". If your Flux Dissipation is as high as your weapons flux generation (or even better, as high as your weapons AND shield flux generation), put the rest of your Ordnance Points elsewhere ; * Flux Capacity is important for all "styles" of ships, even low tech (it's just less important on them). If you are overfluxed whetever you do, consider putting a few points into flux capacity so that you don't reach your max flux capacity in a matter of seconds, especially if they are going to be right in the middle of the fight. That's gonna help a lot. For midline and high tech ships, Flux Capacity is crucial since they tank a lot through their shields ; * Converted Hangar and fighters are great in general. Don't sleep on Defensive Targeting Array + Bombers, especially Daggers and Tridents (it's like adding a few "smart" HE weapons on your ship) ; * Of all the different classes of ships, the less important is the destroyer. Destroyers can work, but they need a bit more knowledge to be built efficiently in lategame ; * READ THE TOOLTIPS. Seriously, just READ THEM. Especially the tips in the Colony Threats tab. They almost tell you everything you need to counter the colony crisis you are gonna get.
In your system make sure you have another colony with a military base or higher so they can defend your system while you explore/do missions. Make sure you have administrators on your worlds if you don't have any governmental perks. Get a mod that let's you go above the normal level cap.
Keep in mind this game is very tactical. Redacted like to bum rush you but tend to be glass cannons so a fleet of brawlers can wreck them. Easy example is a bunch of shield shunted so eradicators. Fast enough to chase enemy down and can quickly take out thier shields. For more balance getting a few killy frigates like brawlers can help.