I've spent a few hours digging through my world to find an aglet to make lightning boots, and still haven't found it due to unlucky worldgen. I feel like the aglet is meant to be something which is nice to find in the first 15 minutes or so of the run, but it just gets annoying when you have to actively look for it later. I know that you can fish for it, but that can be even more tedious and RNG dependent. It would be good if there were some more reliable way to get it slightly later in the game to make it a bit simpler to get lightning/frostspark boots. Maybe make an NPC sell it after Skeletron is defeated, or some way to craft it using Hellstone/something from the Dungeon? I suppose something similar could be done for Climbing Claws and Radar, although I personally don't find the Ninja Gear or the Cell Phone to be as important every run as the lightning boots.