I have something like the Pro-Tec self-stick pads stuck on my Superfeet in my bike shoes. Those are nice and breathable, and if you have an insole you like already they are a great addition. I did have a shoe-store foot-guru put the pads in for me, so I would be sure they went in the right spot. Putting them in the right spot can be tricky, but not too hard. And if it doesn't feel just right, or if one foot needs the pad in a slighty different place, they can be moved.

The forefoot pad with dome would solve the "where do I stick it?" problem. I'd worry about breathability with that slab of silcone, but I have very sweaty feet.

The larger and more expensive silicone insole just looks like too much silicone to me. Oooh, sweaty stinky feet....

So, I'd go by order of cheapest $$ to most expensive $$. Try the self-stick pads first. (I'll post pics of where they are in my shoes and where they should hit the sole of your foot if you need more info).

If you've got an REI or running shoe store near you, try on a pair of Superfeet Berry with the built-in met pad so you can get a feel for where the pad goes. (and if they feel lovely, maybe just get them!)