JMO, sign a FA WR.......there is still SDiggs and ACooper out there.
Trade down and Use rd 1-3 on (playmaker- preferably on D; prefer CB, LB, DE), DT, and RB.
If this team doesn't get a running game, then it doesn't matter who WR2 is. Dak is not Mahomes, Burrow, or Allen. He isn't going to put precise throws 40 yds down the field. He needs a running game. So get the running game first.
And get the D straightened out. Dallas can score 28 a game, and it not matter a bit if the D is giving up 35. Right now, most of the assets and money are tied into the QB, front line, and WR........at least until Parsons signs. This team badly needs DL, LB and RB. It isn't going anywhere till these three positions are made better.
Then and only then would a WR2 make any difference at all. There is still only one ball they are playing with. There are still 5 OL, 1 QB, and 5 skill players on the field. Teams love it when the QB is a playmaker as well, but in general 5-1-5 is the setup. Teams and people don't seem to understand that one group of skill players sets up the other group, and excellent TE's help both the running and passing games. The talent on the team determines the playmakers, but the coaching is the one who either makes it excel or allows it to decline.