It does look like the process has served guys like Hayes and Craig well, although you wonder if maybe it can be broken for them in terms of AAA. Especially with Baz (and maybe to a lesser extent Hearn, who was closer) being used, the clock is now ticking on the window that runs through the 2021 season, and you figure the tear down/rebuild will have to be more substantial at that point. So the focus should really be on taking some more chances for an influx of talent.
I can see more of an argument with pitchers, but for some offensive players, I don't think there's so much of a need to be methodical. We haven't really had a lot of position players who have hit extremely well - Meadows was always hurt, or only performing well in stretches. Maybe Polanco is the closest thing, but as I recall, he had to be sent back a little bit after his debut.
I'd guess the plan for next year at 3B will still be to keep Freese as a bench player, and hope Moran can take some steps forward, especially with consistent power. Neither of those things should block Hayes if he hits well in AAA. Frazier should be playing every day for the rest of the year (he won't), to see what he can hit and field like as an every day player. Newman should at least get folded into the mix at SS a healthy bit, although I imagine we'll sign somebody like Hech as insurance anyways. A guy like Kramer is where it gets more interesting- knowing the Pirates, he'll need to wait for an injury to get his chance, but he's at minimum worth seeing in September this year, and between he, Newman, and especially Frazier, Harrison's money could be reallocated elsewhere at this point. I'd sing a different tune if we didn't have Moran, or I thought we could salvage some trade value from JHay, but I can't see it.
Craig gets more interesting, but for a lot of these guys, we're looking at something like needing management to make the right calls on how much to see of whom, how much patience to have with guys like Moran and Bell, etc., and I can't say I'm very confident there.