Here are the steps I took:
1. Open PDF at regualr 300 dpi import
2. Resize using EDIT > "Image Size" to 72 dpi
3. Use slice tool to select all images I want to crop out
4. Use FILE > "Save for web"
5. I select all images and select which settings I want (either JPG with VERY HIGH compression or GIF standard 256 colors)
6. Export images.
The sizes are HUGE. about 40KB a piece. The dimensions of each image do not exceed 100 pixels on height or width.
Re-open the GIF and do a save for web with the same settings... 4KB.
Re-open JPG and do a save for web at "very high" 40KB, "maximum" 40KB, "low" 40KB.... even when the stats in the lower right of the save for web window state that it should be around 8KB once it is saved.
Please fix this... Every time you guys upgrade PS you seem to break things that have never broken before... There was an issue with "image size" where it would not change the height and width automatically if you changed the DPI... which is now fixed but it was there for a good 3 upgrades since CC was introduced.
First this is a user forum site we are users like you this is not the Adobe feedback site that link is http://feedback.photoshop.com/photoshop_family/
Step 2. Resize using EDIT > "Image Size" to 72 dpi
Did you resample or not. If you do not resample all that changes is the DPI setting the number of image pixels remain the same and a file save if the same typs as open would not change in size,
Why 72 DPI if your resizing for the web you should be concerned about the image pixels how many pixel wide and how many pixel high. Displays do not support an images file DPI setting they use their size pixels. Your image will be different sizes on different displays it depend on the number of pixels a display displays and the displays DPI. You want you image to fit on displays. That usually means an image with no more then640x480 pixels if you want to support old displays.
step 3. Use slice tool to select all images I want to crop out
The slice tool is normally use to dice up an image into pieces that are display as a whole image with different links associated with each piece.
The Crop tool or the marquee tool coupled with image crop should be user to crop an image.
It sound like your editing a multi image pdf file and are saving out image files for each image.
Step 4. Use FILE > "Save for web"
If your editing a multi image document what are you saving when you use save for web and what is the size of your documents canvas.
Step 5. I select all images and select which settings I want (either JPG with VERY HIGH compression or GIF standard 256 colors)
Is that some how connected to Photoshop CC new Generate feature I don't know generate or how you tell generate to save out web files..
Step 6. Export Images.
I thought that was being done with save for web or generate now I really confused about what your doing.
Some examples and screen captures may make what you doing easier to comprehend.
You wrote "There was an issue with "image size" where it would not change the height and width automatically if you changed the DPI... which is now fixed but it was there for a good 3 upgrades since CC was introduced.." It depends on how you set the image size dialog controls. Photoshop will change the width and height when your not resampling for the number of pixels do not change. Width Height and DPI are always linked. This is not the case when your resampling changing the number of pixels, If you have a 5"x7" 300dpi Image and you check resample and change the DPI to 100 DPI the width and height will remain 5"x7" what will happen when you commit the change is Photoshop will in terpit the pixels and the image will go from 1500px by 2100px to 500px by 700px. The print size will remain 5" x 7" at a lower resolution of 100dpi. You should see the width and height pixels numbers change in the image size dialog not the print sizes. However you can also change them and if you do you should also see the pixels width and height change as well go along with the dpi set.