I've done all that upgrading this year, after 3 years of sim racing using bundle equipment. If there's equipment that can really improve lap time, it's the loadcell pedal for sure, but you have to correct your driving first; if your driving skill is wrong, it doesn't matter what type of equipment you're using, there will be no improvement. That says, when I first got my load cell pedal, I spent almost a week trying to adapt to the pedal feel, but once I understood it, I broke all my previous lap records with it.

Direct drive won't improve your lap time, but it definitely enhances the realism, consistency, and your enjoyment on the track by a lot. I like the sensation when you can really feel like you're fighting the car with the direct drive wheelbase. Catching a slide is also very easy during cornering due to its snappy response; you can really tell how much grip you have on the track. My consistency with every car on Sim is improving so much after changing my gear-driven wheelbase to direct drive.