Cars (Ultimate Car Mod): Easy transport of items and allows you to produce gas (Doesn't work with Electrodynamics)
Planes and Helicopters (Simple Plains): Good for exploring and long distance travels. (Doesn't work with Ballistix, but works with MrCrayfish's gun mods to shoot missiles and bullets out of aircrafts.)
Electricity (Electrodynamics): Adds machines to automate processing items and new ores.
Nuclear Stuff (Nuclear Science): Adds Uranium and Plutonium, and some reactors to produce electricity (Works with Electrodynamics)
Explosives! (Ballistix): Ever wanted to make a minefield? Will now you can! Create nuclear weapons for destruction. (Works with Nuclear Science)
Trains! (Ultimate Transport): Create speedy railways to travel back and forth from place to place. And elevators!
Guns (MrCrayfish's Gun Mod and Addition Guns): What is war without guns? Adds plenty of guns to suit your needs. Also attachments!
More storage (Iron chests and Iron Barrels): Upgrade chests and barrels.
Tanks! (Trajan's Tanks): You can't forget your tanks with war! Adds 5 tanks and an Anti-tank artillery.
Security (Security craft): If you have all of this stuff you need to protect it! Adds tons of items to help protect you from intruders.
Boats (Boatload and Fireproof boats): With crimson/warped boats you can ride it on lava! Adds bigger boats for more people as well as furnace powered boats. Attach banners to them too!
More food! (Farmer's delight): Adds more variety to foods, we need something that doesn't involve wear in here.
Furniture and décor (MrCrayfish's Furniture mod and Supplementries): Sit back, relax, and eat in your luxury kitchen that you just made using this mod! Adds a lot of furniture!
Structures! (When Dungeons Arise): Tons more structures to explore and hopefully not die in.
Extras: Voice chat, XP clumps, JEI, and Shulker box tooltip