I say
no! Want to know why? 24/32bpp images can be/are very large because they use the
entire color palette despite image dimensions. If you want your 256 color images to look better when the palette is compressed, use a dithering effect. Best one for smooth(est?) blending would be Floyd-Stienberg. While it may make the images look a tad rough, at a distance it will look fine
Attached is one of the images I made a while back for the JobClass setup screen. Despite it being in 8bpp, from a distance you don't notice it. Everything appears to be smoothly blended because the original was very smooth

Besides, I don't want to have to spend a lot of time downloading 300k+ images if they are all 24/32bpp even if they are only 32x32
Suggestion: If you want things to look better, seperate them into parts and reconstruct them with scripts. Yeah, it may be a pain, but think about the players

Not everyone is fortunate enough to even get broadband services let alone even be able to afford
