For stains, I assume some just give a deeper richer tone. Maybe I'm
wrong. I'm looking for it.


I would never use an oil stain for a deep rich tone. I would use a
dye. I use oil stains for changing tint of things like make Oak look a
little yellower or redder. If you really want to change the color then
using dye is the best. A gel stain or tinted poly is kind of like
painting and can change the color but you hide some of the grain too.
Pigment stains are just not that reliable. I hear all the time that
people hate Minwax because they bought walnut stain, put it on their
maple boards and only ended up with a few places that look dirty and
the rest still looks like maple. The pigment is just ground up
minerals and need to get into the grain to color it. Hard to predict
the outcome. Dyes use metals and are ground like 1000 x finer. Same
principle but get down to almost the molecular level.