Painting colored plastic

I sometimes think some mfgs believe MOST modelers do not paint their models. I base this on the poor color instructions, and on putting all color info at end of instruction sheets.  Only a few companies seem to have any suggestions on when to paint parts.

I remember some kits from the 50's-early 60's that would come molded in several colors. Always seemed a shame to paint over them.

I believe it was pretty much so kids wouldn't have to worry about painting their kits.

Styrene plastic molded in color has a translucent appearance- the color seems to come from within the plastic, not just at the surface, like paint.  So painting does improve appearance.  For a flat surface, a dullcoat spray does help, but painting is always better.

In my experience, unpainted plastic always looks like unpainted plastic.

Especially with reds, there always seems to be a slight translucence that makes it look not quite right when unpainted, even if it's clear-coated.

I feel that all plastic should be painted,just my opinion, you may end up with repaired seams,putty,sanding,and glue marks that need to be covered.It's hard to build the the perfect fitting model avoiding these things,so primer and paint my be necessary to cover up.