My #1 suggestion would be to head over to
https://disneycruiselineblog.com for general DCL info and to sign up for discount announcements. That said...
You're not going to see a lot of discounts during the Wish's maiden year. In general, DCL's discounts are offered mainly on random non-holiday cruises into the Caribbean and Bahamas though they have offered some this past year for more 'peak' destinations and times as they try to fill staterooms through COVID. They offer VGT, OGT, and IGT discounts (Verandah, Outside, and Inside) if you are willing to let Disney choose your stateroom. There are also Military (MTO), Floridian (FLR), and Canadian (CAN) discounts.
Also in general, for high demand cruises the prices only go up and so the best rates you will see will be on the first day you can book. We were/are Platinum and had a cruise to Iceland/Norway in 2015 where the prices just over 6 months out were double what we given at the opening bell. I would guess that while not so acute, pricing will slowly rise for Wish cruises this year. At least until 60-ish days out...assuming there are any left at all.
Other tricks. Anything you want, reserve it as early as you can. Over time we went on fewer and fewer excursions by DCL...but selected ones were completely 'worth it'. The big advantage is that they hold the boat for you if there is a problem. Once we were caught by high winds, unable to get back into Skagway. They opened up a local museum for us and brought in a 'roach coach' that served us amazing fish and chips while we waited to be allowed to return. Another time, Disney 'persuaded' the Vatican to open the Sistine Chapel on a Sunday...the only people in the place were Disney Cruise guests.
If you want main dining, reserve it as early as you can. Same goes for spa appointments, beverage tastings, and character interactions (assuming they still have and book those), and anything else.