You planning to find a better catcher? Jeffers put up 2.7 fWAR in 96 games, 77 as a catcher. Those are some elite numbers, 11th overall when playing C, and all but one of those had at least 15% more games as a catcher than him. If he'd caught as many games as Rautshcman at that pace, he'd outfWAR him by at least half a point, and be the 5th best catcher in the game. What are we expecting to be considered elite?
Wallner is a rookie....who put up 1.9 fWAR in 79 games......is he elite? No. Is he possibly in the top 5-10 among LFers? Yes. He had 41 games as a LF and put up 1.5 fWAR while being a LFer....let's just multiply that by 3, so 123 games, and he's at 4.5 fWAR. That would make him the 2nd best LFer in the game.....I don't know if he can put that up, but maybe 3.5 fWAR...which is 3rd best among LF while playing LF.
Now, you want to fix things? 1B, CF, and DH are your key positions for this team. RF if they let Kepler go, which they won't. 3B if Lewis isn't healthy.....but you shouldn't plan on that, IMO.