Which mods should I instal for my game? [New TS3 playrer]

Wouldn't "Complete Collection" include everything from The Exchange and the worlds as well?

To answer the question, I'd recommend the NRAAS Overwatcher mod for better game performance and less lag, it removes unroutable Sims and other things that clog up the game. Another mod - a lightning mod since the game tends to have really bad lightning - namely Frozen Lighting Mod. I haven't tried it personally, but from what I researched, there's more than one "make lightning better" mod.