Sanji is the boggest strength earned bounty
Boa had 80m but because she controls a country full of warriors, not her individual strength
Robin got it because of her ohara knowledge.
Luffy and.zoro beat small fry to get theur furst bounty
Sanji outright beat jabra, someone that rivaled strongest CP agent in history, withiut havubg a bounty yet
Correction:
1. Infiltrated and deactivated high level Cipher Poll filled Sea Train with high level assets on board.
2. Defeated Jabra.
3. Closed the Gate of Justice, resulting in the Buster Call's failure.
Sanji's first bounty of 77m is for his STRENGTH and BRAIN. His 77m is for those 3 feats. So it's safe to assume that for those 77m, a minimum of 26mil is for his strength alone (1 of the 3 feats).
For defeating Kaku alone, Enies Lobby's Zoro went from 60m to 120m, which means Kaku worth 60m. Let's say Jabra worth a bit less than that.
In conclusion, Enies Lobby's Sanji 77 mil is for both of his strength feat and brain/tactical feat.
In actuality, his strength feat alone is only worth less than 60mil in Enies Lobby (because Jabra is lower than Kaku).
To reflect the parallels with Zoro, Sanji's actual first bounty (for STRENGTH) would be less than 60mil (Jabra's worth and lower than Zoro's first bounty).