I've always thought it was 2020 to be a real contender (90 plus wins on a regular basis), now Gillick may have thought in terms of 85-90 wins, when you're a wild card contender and can win the division in a weak year (no one expected the Nats to go belly up).
When you bring in a lot of young players quickly, unless you get really lucky like the Braves, where you have multiple top prospects all arrive quickly, you go through growing pains, some shine like Rhys, some go up and down and up again like Franco, some have a delayed ETA like Kingery, Alfaro and Crawford, and some just slip and fall (Altherr). It's both a matter of player development and player self-selection (some fail and signal they need to be replaced).
2020 lineup (before FAs):
C Alfaro, Grullon, Knapp (jack of all trades, he's playing 3B at Lehigh)
1B Hoskins (Listi/Cozens as 1B/OF?)
2B Kingery
SS Crawford
3B Franco
LF Williams, Randolph
CF Moniak, Quinn
RF Haseley, Pujols
The lack of depth is IF, none of the LA prospects will probably be past Lehigh or Reading by the end of the 2020 season.
Pitching is where this team will be very deep, and I see multiple pitchers traded for position depth:
SP: Nola, Eflin, Velasquz, Pivetta, Arrieta [Eickhoff, Lively], De Los Santos, Irvin, Suarez, Romero, Seabold, S Sanchez, Medina
RP: Neris, SD, Arano, Ramos, Rios, Davis, Anderson, Gilbert, Singer, McGarry, E Garcia, Dohy, Hammer, Tirado