MechaPilot
Explorer
I always find the "why should I allow _______" questions very odd in forums. We're really not the ones you should be asking. It's your players whom you should be asking.
Now, we can all give generalized responses about the customization offered by feats, multiclassing, or any other optional feature. However, none of our responses are necessarily going to reflect what you would hear from your players.
Additionally, customization can be had within a single class by asking one's DM about switching class or subclass features. And there's always multiclassing, if you allow it. Plus, you could evaluate allowing characters to pick up things from other classes through downtime training; I have done that in the past and plan to use it again in the future.
Now, we can all give generalized responses about the customization offered by feats, multiclassing, or any other optional feature. However, none of our responses are necessarily going to reflect what you would hear from your players.
Additionally, customization can be had within a single class by asking one's DM about switching class or subclass features. And there's always multiclassing, if you allow it. Plus, you could evaluate allowing characters to pick up things from other classes through downtime training; I have done that in the past and plan to use it again in the future.