It's always a painful process for me to save an artwork from Photoshop and Illustrator for the Web to 25 or even 50 kb with adequate quality, even if there are not that many graphic details. Also, it often has strange quality after change-over from 300 to 72 ppi.
Are there general approaches to saving for web with good (as original) quality in small, medium and large sizes?
For example, I need 25k file for client as smallest size (but the problem is that's actually the main size they will use). Here is original vs 25k:
Fonts and vectors look awfully pixelated (scale 800%):
Gradient looks too linear (scale 100%):
(scale 800%):