Some PageSpeed complaints about CB extension

I'm trying to optimize a bit on the site loading speed, and I see a lot of messages coming from CB extensions and modules, this is a page with a CB list showing:
Serve scaled images
/components/com_comprofiler/plugin/templates/bootstrap/images/avatar/nophoto_n.png is resized in HTML or CSS from 150x209 to 26x36. Serving a scaled image could save 30.9KiB (97% reduction).
/images/comprofiler/150_4f722131608ec.jpg is resized in HTML or CSS from 200x150 to 36x27. Serving a scaled image could save 30.8KiB (96% reduction).
/images/comprofiler/75_511e5897f3cbb.png is resized in HTML or CSS from 150x150 to 36x36. Serving a scaled image could save 30.2KiB (94% reduction).
/images/comprofiler/127_504e0bec8a8a8.jpg is resized in HTML or CSS from 300x286 to 36x34. Serving a scaled image could save 29.0KiB (98% reduction).
/images/comprofiler/106_4ec2849d0ab09.gif is resized in HTML or CSS from 200x267 to 27x36. Serving a scaled image could save 21.7KiB (98% reduction).
/images/comprofiler/tn126_5012a7f9f12cb.png is resized in HTML or CSS from 60x80 to 45x45. Serving a scaled image could save 15.1KiB (57% reduction).
/images/comprofiler/82_4e64bbf26f489.jpg is resized in HTML or CSS from 200x266 to 27x36. Serving a scaled image could save 15.0KiB (98% reduction).
/images/comprofiler/tn145_50002334decbe.jpg is resized in HTML or CSS from 48x85 to 45x45. Serving a scaled image could save 8.2KiB (50% reduction).
/images/comprofiler/tn118_509d8a2e73e41.jpg is resized in HTML or CSS from 60x60 to 45x45. Serving a scaled image could save 7.0KiB (44% reduction).
/images/comprofiler/tn127_504e0bec8a8a8.jpg is resized in HTML or CSS from 60x57 to 45x45. Serving a scaled image could save 5.7KiB (41% reduction).
/images/comprofiler/tn150_4f722131608ec.jpg is resized in HTML or CSS from 60x45 to 45x45. Serving a scaled image could save 5.6KiB (26% reduction).
/images/comprofiler/105_4e6a0e02656d4.jpg is resized in HTML or CSS from 200x150 to 36x27. Serving a scaled image could save 5.0KiB (96% reduction).
/images/comprofiler/tn106_4ec2849d0ab09.gif is resized in HTML or CSS from 60x80 to 45x45. Serving a scaled image could save 2.6KiB (57% reduction).
/images/comprofiler/tn159_4faa95c67a2dd.jpg is resized in HTML or CSS from 60x65 to 45x45. Serving a scaled image could save 845B (49% reduction).
/images/comprofiler/tn84_4e6692e3bd555.jpg is resized in HTML or CSS from 60x45 to 45x45. Serving a scaled image could save 495B (26% reduction).
/images/comprofiler/tn78_4e60d59f23e6e.jpg is resized in HTML or CSS from 60x36 to 45x45. Serving a scaled image could save 406B (25% reduction).

Combine images into CSS sprites
/components/com_comprofiler/plugin/templates/bootstrap/images/mini-icons/icon-16-info.png
/components/com_comprofiler/plugin/templates/bootstrap/images/mini-icons/icon-16-required.png

Optimize images
Losslessly compressing /images/comprofiler/150_4f722131608ec.jpg could save 20.6KiB (64% reduction). See optimized version or Save as.
Losslessly compressing /images/comprofiler/tn150_4f722131608ec.jpg could save 20.6KiB (92% reduction). See optimized version or Save as.
Losslessly compressing /images/comprofiler/tn118_509d8a2e73e41.jpg could save 14.5KiB (90% reduction). See optimized version or Save as.
Losslessly compressing /images/comprofiler/127_504e0bec8a8a8.jpg could save 12.6KiB (43% reduction). See optimized version or Save as.
Losslessly compressing /images/comprofiler/tn127_504e0bec8a8a8.jpg could save 12.6KiB (89% reduction). See optimized version or Save as.
Losslessly compressing /images/comprofiler/tn145_50002334decbe.jpg could save 11.5KiB (70% reduction). See optimized version or Save as.
Losslessly compressing /images/comprofiler/tn98_4ee0ed5ea32df.jpg could save 3.0KiB (74% reduction). See optimized version or Save as.
Losslessly compressing /images/comprofiler/106_4ec2849d0ab09.gif could save 612B (3% reduction). See optimized version or Save as.
Losslessly compressing /images/comprofiler/82_4e64bbf26f489.jpg could save 439B (3% reduction). See optimized version or Save as.
Losslessly compressing /images/comprofiler/tn84_4e6692e3bd555.jpg could save 386B (20% reduction). See optimized version or Save as.
Losslessly compressing /images/comprofiler/tn78_4e60d59f23e6e.jpg could save 382B (24% reduction). See optimized version or Save as.
Losslessly compressing /images/comprofiler/tn80_4e60b0060deae.jpg could save 381B (19% reduction). See optimized version or Save as.
Losslessly compressing /images/comprofiler/tn82_4e64bbf26f489.jpg could save 380B (15% reduction). See optimized version or Save as.
Losslessly compressing /images/comprofiler/tn85_4e64a4f7bbe67.jpg could save 377B (22% reduction). See optimized version or Save as.
Losslessly compressing /images/comprofiler/105_4e6a0e02656d4.jpg could save 376B (8% reduction). See optimized version or Save as.
Losslessly compressing /images/comprofiler/tn79_4e74cee6b9cd2.jpg could save 375B (19% reduction). See optimized version or Save as.
Losslessly compressing /images/comprofiler/tn91_4e68fe635c791.jpeg could save 374B (18% reduction). See optimized version or Save as.
Losslessly compressing /images/comprofiler/tn106_4ec2849d0ab09.gif could save 332B (8% reduction). See optimized version or Save as.

Defer parsing of JavaScript
/components/com_comprofiler/js/jquery-1.5.2/jquery-1.5.2.min.js?v=5c3d1f20808e905c (77.4KiB)
/components/com_comprofiler/js/jquery-1.5.2/jquery.validate.min.js?v=5c3d1f20808e905c (18.5KiB)
/component/comprofiler/userslist/Bestyrelse.html?Itemid=1955 (15.2KiB of inline JavaScript)
/components/com_comprofiler/js/jquery-1.5.2/jquery.form.min.js?v=5c3d1f20808e905c (9.5KiB)
/components/com_comprofiler/plugin/user/plug_cbconditional/js/cbconditional.min.js (7.9KiB)
/components/com_comprofiler/js/tabpane.min.js?v=5c3d1f20808e905c (4.4KiB)
/components/com_comprofiler/plugin/user/plug_cbcorefieldsajax/cbcorefieldsajax.min.js?v=a344b731389fd995 (2.2KiB)

First chunk is profile images (full size). Second chunk can't be combined as the images are loaded in by <img> tags directly and not CSS. Third chunk are profile images (thumbnails). Last chunk is various JS libraries that are already minified. Don't see any problem here. Reducing file sizes a couple of bytes isn't going to do anything unless your users are on dial-up.

You should use xdebug and enable profile, profile any slow pages you find, then review the output in Webgrind or similar software to see exactly what is slowing the page down. What slows pages down is server side handling (PHP loops, queries, etc..). Client side data isn't a problem except for users with slow internet, which isn't the case anymore.