Slow Step on Reaction Profile, Pre-exponential Factor

[Silvi_Lybbert_3A]

For example, for a mechanism with three steps and two intermediates, a reaction profile might show three different activation energies (the intermediates at the two dips between). I was thinking at first that the slow step would have the highest activation energy barrier seen on the profile (also seen in textbook problems); however, I reasoned that the slow step may be rate-limiting not because of a high activation energy, but possibly rather because of a lower pre-exponential frequency factor (the intermediate at this step reacting with a reactant might show greater angular dependence). So, I concluded we wouldn't be able to tell for sure what step the slow step is based off of a reaction profile. Is that true? I realize that the rate constant is exponentially dependent on the activation energy, whereas it is not for the pre-exponential frequency factor A, so this means the activation energy barrier is more likely the cause of a step being rate-limiting. --> thus generally, we can infer highest activation energy is the rate-limiting step?
I was wondering if someone could confirm or reject this reasoning. Thank you so much!

[KatarinaReid_3H]

I do not know for sure, but it would make sense that each step within a rxn might get its own A value, especially in a rxn that has many steps. Based on this class and the textbook problems, I do not think we go into that level of depth here though. Great question!