Yeah, clean the base, or give it a good brushing if you don't have the base cleaner. Then wax the crap out of it. It's hard to overwax a new board/pair of skis, and the more wax you are willing to put into it, the better it'll be.
Start with something soft, like Swix CH-10 (or equivalent), or even a base prep wax. Scrape it while still hot the first time (this is a good way to clean the base), then do a normal wax/scrape with a soft wax for the second coat.
Then, do a couple layers of a harder wax, like CH-7 or CH-6 (how cold is it where you ride?). The first layers of soft wax will penetrate your base better and act as a binder for the harder wax. After a total of 4-5 layers of wax, you need to get out on that board.
You only really need to base grind if you have seared your base from ironing too hot or (the real reason for stone grinding) if you want to true it perfectly and get a certain structure.
You can get sufficient structure by running your brass brush *lightly* over the base, once, after the last layer of waxed is scraped and buffed with your softer brush(es). If you don't have brushes, coarse and soft Scotch-Brite pads work in a pinch.
Congrats on the new board.