When you pause, you have the option to "return to map". When you return to map, you keep the special items you collected and hardly use any Time. You can re-enter and collect the same Special Item or two, then exit. The maximum is 9, and you have that number of whichever the last Special Item you collected was. In a casual playthrough, this gives you plenty of Hearts or Shields and is fantastic for struggling new players. In a speedrun, this may be useful for using an ample supply of Bombs on Flotillas or Base Cores or Star Wolf Members, or whatever else could be dealt with much quicker. This also helps greatly reduce the overall urgency of the game.
Also, you can press Select to swap between characters. Having Fox/Falco as your second character gives you 3 free Bombs for Flotillas.