I am able to get through every other part of the game fine enough, but the X-Wing level is just so hard and fast paced, how do you keep a good streak through this part?

I assume you're talking about the 2nd part of the shooter section of the game, last before the death star trench auto-scroller. While the 1st part is arguably much harder to do optimally for the speedrun, the 2nd part gave me a lot of trouble at first just to even survive it without dying. One problem that I was doing was trying to follow the TIE fighters with my cursor and they seem to always get out of reach. A trick you can do is keep your cursor towards the center briefly which can bait the TIE fighters towards the center then do quick jerks towards them to pick them off. There are 2 phases with the horizontal 1st phase somewhat easy. The 2nd phase where they come from all directions will take some more practice.

It depends on if you just want to consistently beat it, or consistently beat it fast. The TIEs come in waves that use two types of flight pattern. When each wave starts, just hold up and right and fire away. The TIEs that come in from the bottom right will fly right into your fire power, while the TIEs that come in from the bottom left will go to the top and eventually move to the right where the other TIEs are/were. That's about 15-20 basically free kills. After these guys are toast, the TIEs will come in groups of three and try to fly in front of you while shooting torpedoes like crazy. You don't HAVE to kill these guys if you don't want to (although you need to kill a certain amount of overall TIEs to advance). Rather, each trio will fly away after 10-20 seconds. So you can just move from corner to corner in a clockwise manner to avoid them until they leave. Once these trios are gone, more TIEs using the first pattern will come back for more free kills. But if you do want to kill the trios, I suggest that you briefly fly in the opposite direction for a second or two and then jerk back toward them for a second. This will bait them into a position where you can shoot them with relative ease (just be careful about those torpedoes). If you have R2-D2 and no shields, avoid the trios until he repairs a block or two of shields.