However, I do think that “lesser” was the correct word, and I will explain why.
First though, I have to explain what the word “lesser” means and does not mean in this context. There are two types of “lesser”. One is what I would call subjectively lesser and one I will call objectively lesser. Subjectively lesser refers to things such as intelligence level, social skills and knowledge. Objectively lesser means that a person is not as good a person.
A person’s objective goodness is based on the extent to which they use their bechira and therefore can only be measured by Hashem, since no one knows anyone else’s potential.
Subjective lesserness is not a reflection of how good someone is. It is simply a measure of the abilities that Hashem gave the person (in certain areas) and is not necessarily in the person’s control and therefore is not a reason for someone to think less of anyone else.
How good a person is has to do with the difference between their actions and their potential. Therefore, if two people have the same actions but one is lesser in terms of subjective greatness, this would actually mean that he is greater in terms of objective greatness.
As the Ramban points out in The Igeres HaRamban, if you are greater than someone else, you should not look down on them; this simply means that you have greater responsibilites.
So if two people are performing the same actions but one has more potential, this actually means he is “lesser” in the way that really counts.
I used to refrain from ever thinking that I was “better” (ie: blessed with more abilities in any area) since it seemed to be snobby, and I thought it was wrong to think that way. However, I realized at a certain point that that is simply not the correct approach, and thinking that way was actually more likely to lead to my thinking badly of others.
A person has to be aware of his talents (while acknowledging that they are from Hashem and not his own doing), so that he can be aware of his additional responsibilities (as the Ramban points out).
Likewise, it is sometimes necessary to be aware of other’s shortcomings in order not to expect too much for them and to be able to judge them favorably and in order to understand them better.
You are not doing someone else a favor if you expect things from them that they are not capable of. For example, if you are more intelligent than someone else, it is very important to realize that when you are dealing with them so that you don’t assume that something is obvious to them just because it’s obvious to you (a mistake that I often make). It is not nice to the person to do that because then you assume that they were deliberately being mean when they might not have been.