Mmm... Optimising Tiki to work per your hosting plan requirement is "always" possible but it will require time and skills (both = money). This is not something that can be easily fixed and it seems specific to your environment.
Most of us (I do) have pages with more than 20 images or 22 processes and no problem.
Did you try to display you images a different way.
The plugin img has an option to display ALL the images from a file gallery.