The insoles typically are the first thing that gets worn out.
Insoles will eventually flatten from the weight of your body. this will then put downward pressure on your arches. Insoles get flattened from use and no longer hold your heel in the correct place. I've had tough and irritating times when my insoles got so flat that, in wet conditions, they would get folded and would go towards my toes, making walking a miserable experience.
If I am gonna look for an insole, I'd definitely go for some product that has a more thicker layer, but fits in well. This can be more-so-ever called as the insole for comfort. Which are usually made up of soft foam and provide shock absorption and cushioning.
You should go with such class of insole if you are going through some sort of pain in Toes after a long walk, more specifically a downhill walk, and worst case if you are suffering from Blisters.
If I am looking for an insole typically for support, and not because its just getting thinner, I'll go for some Sports Insole or Support Insole. These typically should be used in case you are planning for a run or a trail-run. These are less comfortable as compared to Comfort Insoles. These typically features arch support. This help with Overpronation problems as well, and I found them more useful for someone like me who has an odd size of feet that doesn't fit in a standard shoe size. The arch part of the insole helped me with problem that I faced that in my shoes the feet slips forward when I run, causing a toe pain, worst case sometimes a black toe, just because I had a bigger size of a shoe than what suits me.
There is another thing called Heel pads. There are used to lift your heel slightly higher than what a normal insole would do. These are typically meant to reduce the discomfort with Heel injuries. I have never tried them at all.
: This type of insoles is designed to decrease the pressure on the metatarsal bones. They fit under the balls of the feet and are recommended for athletes who often run uphill or experience pain in their mid-foot. These never made any sense to me but I have seen so many people using them for ascends and removing them on a descend. May be this idea of taking off shoes just for that matter never made sense to me.
In general, I were you, I would look for insoles that offer a higher arch to hold the heel in place which will help in supporting the leg and keeping it steady rather than having the entire pressure slipped to toe on a descend. The cushion part is up to you to decide on.