This is nearly impossible to answer. As you say, everyone is different. Different in terms of not just how we respond to a medication in general but also in terms of how we react to a particular dose size of a certain medication. For instance, I could say I had no side effects to Keppra but lots to Tegretol while someone else might say Keppra was horrible for them but Tegretol was okay . . . but that is not taking into account the size of the dose, the frequency of dosing, other seizure and non-seizure medications that the person is taking, non-prescription medications and supplements being consumed, differences in metabolism, difference in body size of two people, etc.
In my case I have had side effects to what would have been low doses of a particular medication, while others on here were taking 2x and 3x that amount with no side effects. I have also been on more typical doses of other medications and had no side effects whereas others here complained when they were on even lower doses than I was.
If you are planning on using responses here as a guide as to what to choose: I wouldn't advise it. This is something to be worked on with your doctor, who will know what medication to choose based on seizure type, seizure cause (if known), and how you have responded to particular medications to date (some work on calcium channels, some on potassium channels, some influence GABA functioning, etc.). And from there, trial and error to achieve a balance between seizure control and tolerability of side effects.