This team is not going anywhere until they develop players like Haseley, Moniak, Bohm and Stott, and hopefully hit on one or two others like Stephen, Grullon, etc. Not just to fill out the lineup and bench, but enough surplus talent for a trade or two.
And they also need to develop some young pitchers. Even if you buy pitching, odds are it'll break down. Safety in numbers.
They don't have that much money, even with the RPs gone, they'll almost certain add one or two veteran RPs, Realmuto will cost $20+M to extend, Arrieta has one more year, so we're talking at best one major FA acquisition - and say it's a top pitcher on an overpay, what will that get you, 3-4 more wins next year (4-5 WAR pitcher at $25-30M)? 88--89 wins will not take the division from the Braves.
You can't buy your way into contention unless you're really, really lucky (no injuries and all your FAs play up to your expectations) because you need 40+ WAR and 20 WAR on the market would get you close to the luxury tax.