Thank you for your replies. Another question though (sorry). I noticed that a lot of people remap their controls so that directional jumping is disabled, Z is attack instead of grab and they usually map grab to either x or y (I think usually y?) Could you explain the reasoning behind this? I've used directional jumping for as long as I've played this game and I'm very used to it. Is it really crucial to jump using the buttons?
What you listed isn't a typical control scheme. However, it is fairly common to turn tap jump off, but hardly necessary. One reason people turn it off is if they use G&W or Sonic or some other character that can second jump AFTER they up B, since with tap jump on a lot of times you will accidentally waste your second jump right before you up B. Tap jump does however make it easier to do certain things out of shield. Since you can cancel your jump squat frames into up smash or up B, you can use the same up that causes jump squat as the up in up B / up A for up B and up smash (jump squat is an animation before you leave the ground that lasts between 2-6 frames depending on character (or 8 if you're Bowser)). (Note: for up smash you have to let go of shield before hitting A or you will grab). Even if you have tap jump on though, there are definitely times where it's best to use the jump button, simply because it doesn't affect your control stick inputs. For example it's much harder imo to rar with tap jump (in a run, which happens after the initial dash, you can tap flick backwards and then immediately hit jump and resume holding forwards, which will make you jump backwards while still maintaining your forward momentum. Hence the name "reverse aerial rush," or rar. In general, using the jump button makes it easier to keep influencing your character's momentum while in the air.
Setting Y to grab isn't typical, but some people set a shoulder button (L, R, or Z) to attack so that they can DACUS (dash attack cancel up smash). DACUS is performed by hitting down c-stick during a dash or run and then inputting up A or up Z (A meaning "attack and z meaning "grab" here). Grab is read as "attack + shield," so it can work, however it makes the timing tighter by one frame for all characters and closes the window completely for others. Since DACUS cannot be used by every character, changing your controls here kinda depends on who you play as.
Personally my control scheme is:
R: jump (in case I use Mewtwo so I can hover in any direction while attacking with c-stick... it also helps for doing out of shield things for when I have tap jump off)
Y: special (to make it closer to the jump button)
B: taunt/footstool
tapjump: undecided... I change this all the time.