If you think about PD and Flak, then a more expensive explosive drone is not such a good idea.
Any advantage you might get is rendered null by the upped cost, when the function and weaknesses remain the same.
You're essentially saying "missiles, but you lose more resources" sure, they could be perhaps set to have a custom approach vector, but if the ship is prepared for getting hit at an odd angle (which is again something already done by missiles) then the effects are the same at higher costs.
And you can't just make it more explosive because you have to pay attention to balance.
And even so, the idea still boils down to "bigger nuke" or "better missile". Which is nothing new.
Perhaps you could explain what you imagine with "programmable" and we could get a better idea of what you have in mind.