It really depends on the particular wood. I have had maple stocks that were scraped, and didn't need to have the whiskers raised, and removed, because nothing came up when we wiped the stock with a wet rag. Ohers, you need to whisker, and then I use the scrapers again to remove the whiskers. Sand paper just seems to pull up more whiskers, until you start getting grooves where the soft wood is located. Same with using OOOO steel wool, but in that case, you can also get bits of steel wool embedded in the soft growth rings. Once I get to using scrapers I don't switch back to anything else.
As to burnishing, wait to do this after you stain the wood. And don't use a lot of force to burnish the stock. Soft woods collapse and form wavy lines , when you use too much force. Use a firm hand, but just rub the wood, so that it gets a slick shine to its surface. If you burnish before you stain, its much harder to get the wood to take the stain( Not impossible, but harder.)
( Hint: If you heat up the stain before applying it to the wood, it will stain even burnished wood. You may get some whiskers raised doing that, but light scraping( whisk the scraper like you are using a whisk broom to get lint off a jacket) , and then burnishing the wood again will resolve the issue.)