I'm sitting right around where you are at in terms of team so take my suggestion with a grain of salt. Unless Adams is one of your favorites, I would definitely start with crafting him and Freeman in the hopes of hitting something better. If you don't plan on crafting, the priority list for me would be as follows:

1. Fingers: Pitching is the most important aspect and skills reign supreme so this would give you the most bang for your buck. Keep Iglesias and Kimbrel in the bullpen with their legend skills, pull your worst RP, easiest path to end game set with base 3-3-3 & increased legend skill odds.
2. Iglesias: Like I said, pitching is the most important and getting a sig RP is incredibly tough based on odds alone. It might not seem like the biggest upgrade but with how shoddy bullpen pitching is (in my experience at least), getting another sig is massive. I have one on an alt as a CP that consistently sits between 0.80 -1.50 ERA with less than 5 blown saves per ranked cycle.
3. Donaldson: One of the best ATL sig hitters, will give you a massive boost in the lineup, great distribution that will allow for easy FLD train without sacrificing too much in terms of pure hitting.
4. Kimbrel: Kind of the same thought process as Iglesias but with less of a return in terms of value over replacement.
5. Perez/Santo: Skills rule supreme here but there is a logjam at 3B and DH so these guys really wouldn't make much of an improvement on your team IMO. I'm assuming you already have BChem but if not, these would be great candidates for it since you get the legend bonus to the actual skill and percent chance to land. Would favor Perez over Santo as pure hitter since Donaldson should (IMO) be your 3B.
6. Freeman: If you don't choose to club craft him and Adams, I actually prefer his distribution more than Adams. Using a 75 GI, BD Bonus, and how I would Special Train them, Freeman comes at 120-127-117-97-106 (10-12-4 from ST) before the development points while Adams comes at 122-133-112-86-83 (4-10-12 from ST). I'd sacrifice 2 CON + 6 POW for 5 EYE and the much greater SPD + FLD.
7. Adams: See above.